Bottle closure assembly including a polyethylene composition

ABSTRACT

The present disclosure describes bottle closure assemblies which are made at least in part with a polyethylene composition having good processability, good organoleptic properties and good dimensional stability. The bottle closure assembly includes a cap portion, an elongated tether portion, and a retaining means portion. The retaining means portions engages a bottle neck or an upper portion of a bottle. The elongated tether portion connects at least one point on the cap portion to at least one point on the retaining means portion so as to prevent loss of the cap portion from a bottle.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. Non-Provisional applicationSer. No. 16/202,565, filed Nov. 28, 2018, which claims benefit of thefiling date of U.S. Provisional Application No. 62/591,911, which wasfiled on Nov. 29, 2017, the contents of both of which are incorporatedherein by reference in their entirety.

TECHNICAL FIELD

The present disclosure is directed to bottle closure assemblies whichare made at least in part with a polyethylene composition having goodprocessability, good organoleptic properties, and good dimensionalstability. The bottle closure assembly includes a cap or closureportion, a tether portion, and a retaining means portion.

BACKGROUND

The manufacture of simple one-piece closures using high densitypolyethylene compositions is well known to persons skilled in the art.

Bottle closure systems and designs incorporating an integrated tetheringmeans, which secures a cap portion to a bottle after the cap portion hasbeen removed from a bottle opening are also well known. Such designstypically involve molding processes which present a more complicated andlonger flow path for a chosen plastic material relative to simpleone-piece closure designs. As such, it would be beneficial to maketethered closure systems using a thermoplastic material which shows goodperformance in molding applications, especially those which involvelonger and more tortuous flow paths in a mold. It would also beadvantageous to make a tethered closure system using a material that hassufficient stress crack resistance and flexibility, as the tetheringportion would need to be both strong enough to prevent loss of the capportion once it has been removed from a bottle opening, and flexibleenough to allow the tethering portion to be formed or bent into suitableclosure system designs.

SUMMARY

The present disclosure concerns bottle closure assemblies including acap portion, a tether portion, and a retaining means portion, where thebottle closure assembly is made at least in part from a polyethylenecomposition having good processability, good organoleptic properties,good dimensional stability, and acceptable stress crack resistance.

Accordingly, an embodiment of the present disclosure provides a bottleclosure assembly which includes a cap portion, a tether portion, and aretaining means portion, the bottle closure assembly being made at leastin part from a polyethylene composition comprising: (1) 10 to 70 weightpercent (wt. %) of a first ethylene copolymer having a melt index I₂, of10 g/10 min or less; and a density of from 0.920 to 0.960 g/cm³; and (2)90 to 30 wt. % of a second ethylene copolymer having a melt index I₂, ofat least 50 g/10 min; and a density higher than the density of the firstethylene copolymer, but less than 0.970 g/cm³; wherein the ratio(SCB1/SCB2) of the number of short chain branches per thousand carbonatoms in the first ethylene copolymer (SCB1) to the number of shortchain branches per thousand carbon atoms in the second ethylenecopolymer (SCB2) is greater than 0.5.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A shows an embodiment of a bottle closure assembly fitted to abottle opening and in a “closed” or “sealed” position. FIG. 1B shows anembodiment of a bottle closure assembly as a cap portion is rotated inorder to bring about its removal from a bottle opening. FIG. 1C shows anembodiment of a bottle closure assembly after a cap portion has beenremoved from a bottle opening. FIG. 1C shows how an elongated tetherportion connects at least one point on a cap portion to at least onepoint on a retaining collar portion once a cap portion has been removedfrom a bottle opening.

FIG. 2A shows an embodiment of a bottle closure assembly fitted over abottle opening and before a cap portion has been removed from a bottle.FIG. 2B shows an embodiment of a bottle closure assembly after a capportion has been removed from a bottle opening. FIG. 2B also shows howan elongated tether portion connects at least one point on a cap portionto at least one point on a retaining collar portion once a cap portionhas been removed from a bottle opening, thereby preventing its loss.

FIG. 3A shows an embodiment of a bottle closure assembly. FIG. 3B showsan embodiment of a bottle closure assembly after a cap portion has beenremoved from a bottle opening. FIG. 3B also shows how an elongatedtether portion connects at least one point on a cap portion to at leastone point on a retaining collar portion once a cap portion has beenremoved from a bottle opening, thereby preventing its loss. FIG. 3Cshows how an elongated tether portion connects at least one point on acap portion to at least one point on a retaining collar portion once acap portion has been removed from a bottle opening. FIG. 3C furthershows that a bottle can be a carton, a container, or any other suitablecontainment vessel which has or is fitted with an aperture or openingwhich can be covered or sealed using a bottle closure assembly.

FIG. 4A shows an embodiment of a bottle closure assembly in the absenceof a bottle. The bottle closure assembly has a cap portion, an elongatedtether portion, and a retaining collar portion. FIG. 4B shows anembodiment of a bottle closure assembly fitted over a bottle opening andbefore a cap portion has been removed from a bottle opening. FIG. 4Cshows an embodiment of a bottle closure assembly after a cap portion hasbeen removed from a bottle opening.

FIG. 5A shows an embodiment of a bottle closure assembly in the absenceof a bottle. FIG. 5B shows an embodiment of a bottle closure assembly asa cap portion is rotated in order to bring about its removal from abottle opening.

FIG. 6A shows an embodiment of a bottle closure assembly which fits overa bottle opening. FIG. 6B show an embodiment of a bottle closureassembly after a cap portion has been removed from a bottle opening.FIG. 6B also shows how an elongated tether portion connects at least onepoint on a cap portion to at least one point on a retaining collarportion once a cap portion has been removed from a bottle opening.

FIG. 7A shows an embodiment of a bottle closure assembly fitted to abottle opening and in a “closed” or “sealed” position. FIG. 7B shows anembodiment of a bottle closure assembly after a cap portion has beenremoved from a bottle opening. FIG. 7B also shows how an elongatedtether portion connects at least one point on a cap portion to at leastone point on a retaining collar portion once a cap portion has beenremoved from a bottle opening.

FIG. 8 shows the balance of processability and environmental stresscracking resistance (ESCR) for various polyethylene compositions andother resins as demonstrated by a plot of the processability indicator(100/η at 10⁵ s⁻¹ and 240° C.) against the ESCR B100.

FIG. 9 shows the balance of processability and impact strength forvarious polyolefin compositions and other resins as demonstrated by aplot of the Notched Izod Impact Strength (J/m) against theprocessability indicator (100/η at 10⁵ s⁻¹ and 240° C.).

FIG. 10 shows a graph of the dimensional stability of various polyolefincompositions and other resins, where dimensional stability isdemonstrated by a plot of the TD/MD shrinkage ratio (for an injectionmolded disk of circular shape) against post-molding time (in hours).

FIG. 11 shows the balance of tensile strength and processability forvarious polyolefin compositions and other resins as demonstrated by aplot of the tensile ultimate strength (MPa) against the processabilityindicator (100/η at 10⁵ s⁻¹ and 240° C.).

FIG. 12 shows the balance of tensile elongation and processability forvarious polyolefin compositions and other resins as demonstrated by aplot of the tensile ultimate elongation (in percent) against theprocessability indicator (100/η at 10⁵ s⁻¹ and 240° C.).

FIG. 13A shows a perspective view of a closure having a tether proxy.FIG. 13B shows a front elevation view of a closure having a tetherproxy. In FIGS. 13A and 13B a tether proxy connects a cap portion to atamper evident band.

FIG. 14A shows a perspective view of a closure having a tether proxyafter much of the tamper evident band has been removed. In FIG. 14A atether proxy connects a cap portion to the remaining section of thetamper evident band.

FIG. 14B shows a front elevation partial cross-sectional schematic viewof a closure having a tether proxy and being mounted on a pre-form forshear deformation testing. Prior to mounting the closure on thepre-form, much of the tamper evident band was removed. The tether proxyconnects a cap portion to the remaining section of the tamper evidentband. To measure shear deformation of the tether proxy, the remainingsection of the tamper evident band is clamped in a stationary positionto the pre-form, while the cap portion is rotated within a torquetester, as shown.

FIG. 14C shows a side elevation partial cross-sectional schematic viewof a closure having a tether proxy and being mounted on a pre-form fortear deformation testing. The tamper evident band was deflected down andaway from the cap portion, while leaving the tether proxy intact. Thetether proxy connects the cap portion to the downwardly deflected tamperevident band. To measure tear deformation of the tether proxy, thedownwardly deflected tamper evident band is clamped in a stationaryposition to the pre-form, while the cap portion is rotated within atorque tester, as shown.

FIGS. 15A and 15B show a perspective view and a front elevation viewrespectively, of a tether proxy after much of the cap portion and muchof the tamper evident band have been removed. To measure tensiledeformation of the tether proxy, the remaining section of the capportion and the remaining section of the tamper evident band are eachclamped and then drawn apart in a vertical direction, within a tensiletester, as shown.

DETAILED DESCRIPTION OF THE DISCLOSURE

Any suitable bottle closure assembly design including a cap portion or aclosure portion, a tether portion, and a retaining means portion iscontemplated for use in the present disclosure, so long as it is made atleast in part using a polyethylene composition as described herein. Somespecific non-limiting examples of suitable bottle closure assemblies foruse in the present disclosure are disclosed in U.S. Pat. Nos. 3,904,062;4,474,302; 4,557,393; 4,564,114; 4,573,602; 4,583,652; 4,805,792;5,725,115; 8,443,994; 8,720,716; 9,493,283; and 9,776,779; U.S.Application Publication Nos. 2004/0016715 and 2008/0197135; U.S. DesignPatent No. D593,856; and WO 2015/061834; all of which are incorporatedherein by reference. For further reference, some bottle closure assemblydesigns which may be used in embodiments of the present disclosure areshown in FIGS. 1-7 .

An embodiment of the disclosure is a bottle closure assembly including:a cap portion, a tether portion, and a retaining means portion, the capportion being molded to reversibly engage and cover a bottle opening,the retaining means portion being molded to irreversibly engage a bottleneck or an upper portion of a bottle, and where the tether portionconnects at least one point on the cap portion to at least one point onthe retaining means portion, wherein the cap portion, optionally thetether portion, and optionally the retaining means portion are made froma polyethylene composition including: (1) 10 to 70 wt. % of a firstethylene copolymer having a melt index I₂, of 10 g/10 min or less; and adensity of from 0.920 to 0.960 g/cm³; and (2) 90 to 30 wt. % of a secondethylene copolymer having a melt index I₂, of at least 50 g/10 min; anda density higher than the density of the first ethylene copolymer, butless than 0.970 g/cm³; wherein the ratio (SCB1/SCB2) of the number ofshort chain branches per thousand carbon atoms in the first ethylenecopolymer (SCB1) to the number of short chain branches per thousandcarbon atoms in the second ethylene copolymer (SCB2) is greater than0.5.

An embodiment of the disclosure is a bottle closure assembly including:a cap portion, an elongated tether portion, and a retaining meansportion, the cap portion being molded to reversibly engage and cover abottle opening, the retaining means portion being molded to irreversiblyengage a bottle neck or an upper portion of a bottle, and the elongatedtether portion being molded to connect at least one point on the capportion to at least one point on the retaining means portion, whereinthe cap portion, optionally the elongated tether portion, and optionallythe retaining means portion are made from a polyethylene compositionincluding: (1) 10 to 70 wt. % of a first ethylene copolymer having amelt index I₂, of 10 g/10 min or less; and a density of from 0.920 to0.960 g/cm³; and (2) 90 to 30 wt. % of a second ethylene copolymerhaving a melt index I₂, of at least 50 g/10 min; and a density higherthan the density of the first ethylene copolymer, but less than 0.970g/cm³; wherein the ratio (SCB1/SCB2) of the number of short chainbranches per thousand carbon atoms in the first ethylene copolymer(SCB1) to the number of short chain branches per thousand carbon atomsin the second ethylene copolymer (SCB2) is greater than 0.5.

An embodiment of the disclosure is a bottle closure assembly includingan integrally molded: cap portion, tether portion, and retaining meansportion; the cap portion being molded to reversibly engage and cover abottle opening, the retaining means portion being molded to irreversiblyengage a bottle neck or an upper portion of a bottle, and the tetherportion being molded to connect at least one point on the cap portion toat least one point on the retaining means portion; wherein theintegrally molded: cap portion, tether portion and retaining meansportion are made from a polyethylene composition including: (1) 10 to 70wt. % of a first ethylene copolymer having a melt index I₂, of 10 g/10min or less; and a density of from 0.920 to 0.960 g/cm³; and (2) 90 to30 wt. % of a second ethylene copolymer having a melt index I₂, of atleast 50 g/10 min; and a density higher than the density of the firstethylene copolymer, but less than 0.970 g/cm³; wherein the ratio(SCB1/SCB2) of the number of short chain branches per thousand carbonatoms in the first ethylene copolymer (SCB1) to the number of shortchain branches per thousand carbon atoms in the second ethylenecopolymer (SCB2) is greater than 0.5.

An embodiment of the disclosure is a bottle closure assembly includingan integrally molded: cap portion, elongated tether portion, andretaining means portion; the cap portion being molded to reversiblyengage and cover a bottle opening, the retaining means portion beingmolded to irreversibly engage a bottle neck or an upper portion of abottle, and the elongated tether portion being molded to connect atleast one point on the cap portion to at least one point on theretaining means portion; wherein the integrally molded: cap portion,elongated tether portion, and retaining means portion are made from apolyethylene composition including: (1) 10 to 70 wt. % of a firstethylene copolymer having a melt index I₂, of 10 g/10 min or less; and adensity of from 0.920 to 0.960 g/cm³; and (2) 90 to 30 wt. % of a secondethylene copolymer having a melt index I₂, of at least 50 g/10 min; anda density higher than the density of the first ethylene copolymer, butless than 0.970 g/cm³; wherein the ratio (SCB1/SCB2) of the number ofshort chain branches per thousand carbon atoms in the first ethylenecopolymer (SCB1) to the number of short chain branches per thousandcarbon atoms in the second ethylene copolymer (SCB2) is greater than0.5.

An embodiment of the disclosure is a bottle closure assembly includingan integrally molded: cap portion, elongated tether portion, andretaining collar portion; the cap portion being molded to reversiblyengage and cover a bottle opening, the retaining collar portion beingmolded to irreversibly engage a bottle neck or an upper portion of abottle, and the elongated tether portion being molded to connect atleast one point on the cap portion to at least one point on theretaining collar portion; wherein the integrally molded: cap portion,elongated tether portion, and retaining collar portion are made from apolyethylene composition including: (1) 10 to 70 wt. % of a firstethylene copolymer having a melt index I₂, of 10 g/10 min or less; and adensity of from 0.920 to 0.960 g/cm³; and (2) 90 to 30 wt. % of a secondethylene copolymer having a melt index I₂, of at least 50 g/10 min; anda density higher than the density of the first ethylene copolymer, butless than 0.970 g/cm³; wherein the ratio (SCB1/SCB2) of the number ofshort chain branches per thousand carbon atoms in the first ethylenecopolymer (SCB1) to the number of short chain branches per thousandcarbon atoms in the second ethylene copolymer (SCB2) is greater than0.5.

An embodiment of the disclosure is a bottle closure assembly including:a cap portion, an elongated tether portion, and a retaining collarportion, the cap portion being molded to reversibly engage and cover abottle opening, the retaining collar portion being molded toirreversibly engage a bottle neck or an upper portion of a bottle, theelongated tether portion including a tether strip which is frangiblyconnected along a portion of its upper edge to a descending annular edgeof the cap portion and which is frangibly connected along a portion ofits lower edge to an upper annular edge of the retaining collar portion,the tether strip being integrally formed with and connected at one endto at least one point on the cap portion and integrally formed with andconnected at another end to at least one point on the retaining collarportion, the frangible sections being breakable when the cap portion isremoved from a bottle opening, but where the cap portion remainsconnected to the retaining collar portion via the tether strip; whereinthe cap portion, the elongated tether portion, and the retaining collarportion are integrally molded from a polyethylene composition including:(1) 10 to 70 wt. % of a first ethylene copolymer having a melt index I₂,of 10 g/10 min or less; and a density of from 0.920 to 0.960 g/cm³; and(2) 90 to 30 wt. % of a second ethylene copolymer having a melt indexI₂, of at least 50 g/10 min; and a density higher than the density ofthe first ethylene copolymer, but less than 0.970 g/cm³; wherein theratio (SCB1/SCB2) of the number of short chain branches per thousandcarbon atoms in the first ethylene copolymer (SCB1) to the number ofshort chain branches per thousand carbon atoms in the second ethylenecopolymer (SCB2) is greater than 0.5.

An embodiment of the disclosure is a bottle closure assembly including:a cap portion, an elongated tether portion, and a retaining collarportion, the cap portion being molded to reversibly engage and cover abottle opening, the elongated tether portion including a tether stripwhich is frangibly connected along a portion of its upper edge to adescending annular edge of the cap portion and which is frangiblyconnected along a portion of its lower edge to an upper annular edge ofthe retaining collar portion, the tether strip being integrally formedwith and connected at one end to at least one point on the cap portionand integrally formed with and connected at another end to at least onepoint on the retaining collar portion, the frangible sections beingbreakable when the cap portion is removed from a bottle opening, butwhere the cap portion remains connected to the retaining collar portionvia the tether strip; wherein the cap portion, the elongated tetherportion, and the retaining collar portion are integrally molded from apolyethylene composition including: (1) 10 to 70 wt. % of a firstethylene copolymer having a melt index I₂, of 10 g/10 min or less; and adensity of from 0.920 to 0.960 g/cm³; and (2) 90 to 30 wt. % of a secondethylene copolymer having a melt index I₂, of at least 50 g/10 min; anda density higher than the density of the first ethylene copolymer, butless than 0.970 g/cm³; wherein the ratio (SCB1/SCB2) of the number ofshort chain branches per thousand carbon atoms in the first ethylenecopolymer (SCB1) to the number of short chain branches per thousandcarbon atoms in the second ethylene copolymer (SCB2) is greater than0.5.

An embodiment of the disclosure is a bottle closure assembly including:a cap portion, a tether portion, and a retaining means portion, the capportion being molded to reversibly engage and cover a bottle opening,the retaining means portion being molded to irreversibly engage a bottleneck or an upper portion of a bottle, and where the tether portionconnects at least one point on the cap portion to at least one point onthe retaining means portion, wherein the cap portion, optionally thetether portion, and optionally the retaining means portion are made froma polyethylene composition including: (1) 10 to 70 wt. % of a firstethylene copolymer having a melt index I₂, of from 0.1 to 10 g/10 min; amolecular weight distribution M_(w)/M_(n), of less than 3.0; and adensity of from 0.930 to 0.960 g/cm³; and (2) 90 to 30 wt. % of a secondethylene copolymer having a melt index I₂, of from 50 to 10,000 g/10min; a molecular weight distribution M_(w)/M_(n), of less than 3.0; anda density higher than the density of the first ethylene copolymer, butless than 0.966 g/cm³; wherein the density of the second ethylenecopolymer is less than 0.037 g/cm³ higher than the density of the firstethylene copolymer; the ratio (SCB1/SCB2) of the number of short chainbranches per thousand carbon atoms in the first ethylene copolymer(SCB1) to the number of short chain branches per thousand carbon atomsin the second ethylene copolymer (SCB2) is greater than 1.0; and whereinthe polyethylene composition has a molecular weight distributionM_(w)/M_(n), of from 2 to 7; a density of at least 0.950 g/cm³; a highload melt index I₂₁, of from 150 to 400 g/10 min; a Z-average molecularweight Mz, of less than 300,000; a melt flow ratio I₂₁/I₂, of from 22 to50; a stress exponent of less than 1.40; and an ESCR Condition B (100%IGEPAL® CO-630) of at least 3.5 hrs.

IGEPAL® CO-630 is a polyoxyethylene (9) nonylphenylether which has anaverage M_(n) of 617 and the structure below and is available fromSIGMA-ALDRICH®.

When integrally molded the bottle closure assembly presents long flowpaths for a plastic material to fill during manufacturing. In thepresent disclosure, the term “integrally molded” means that thatcomponents referred to are molded in a single continuous mold.

Generally, the cap portion is molded to reversibly engage and cover abottle opening or aperture from which a liquid or other type offoodstuffs can be dispensed and so is removable therefrom.

Generally, the retaining means portion, which may in an embodiment ofthe disclosure may be a retaining collar portion, is generally not to beremoved, or is not easily removable from a bottle and in embodiments ofthe disclosure, the retaining collar engages a bottle neck, or an upperportion of a bottle.

Generally, the tether portion, which may in an embodiment of thedisclosure be an elongated tether portion, connects at least one pointof the cap portion to at least one point on the retaining means portion,so that when the cap portion is removed from a bottle opening, the capportion remains flexibly fixed to the bottle via the tether portion andthe retaining means portion.

In the present disclosure, the terms “bottle”, “container”, “jar”,“carton”, “pouch”, “package” and the like may be used interchangeably.That is, a “bottle closure assembly” may also be considered a “containerclosure assembly”, a “jar close assembly”, a “carton closure assembly”,a “pouch closure assembly”, a “package closure assembly” and the like. Aperson skilled in the art will understand that a “bottle closureassembly” as described in the present disclosure can be used to close orseal a number of different types of structural containers havingdifferent designs and contours.

The terms “cap”, “closure”, “closure portion”, “cap portion” and thelike, are used in the present disclosure to connote any suitably shapedmolded article for enclosing, sealing, closing, or covering etc., asuitably shaped opening, a suitably molded aperture, an open neckedstructure, or the like used in combination with a container, a bottle, ajar and the like.

In an embodiment of the disclosure, the retaining means portion canreversibly or irreversible engage a bottle neck, a shoulder section of abottle, or an upper portion of a bottle, or a fitment (e.g., a fitmenton a pouch or a carton).

In an embodiment of the disclosure, the retaining means portion can alsoserve as a tamper evident band (TEB).

In the present disclosure, the term “bottle neck” should be construed tomean a bottle neck per se but also any sort of similar or functionallyequivalent structure such as a spout, a spigot, a fitment, or the like.

In an embodiment of the disclosure, the retaining means portion ismolded or shaped to reversibly or irreversible engage a bottle neck, ashoulder section of a bottle, or an upper portion of a bottle.

In an embodiment of the disclosure, the retaining means portion is aretaining collar portion which reversibly or irreversibly engages abottle neck, a shoulder section of a bottle, or an upper portion of abottle.

In an embodiment of the disclosure, the retaining collar portion iscircularly or annularly shaped so as to reversibly or irreversiblyengage a bottle neck, a shoulder section of a bottle, or an upperportion of a bottle.

In an embodiment of the disclosure, the bottle closure assembly includesa cap portion, a tether portion, and a retaining means portion where thecap portion, the tether portion, and the retaining means portion are allintegrally molded in one piece.

In an embodiment of the disclosure, the bottle closure assembly includesa cap portion, a tether portion, and a retaining collar portion wherethe cap portion, the tether portion, and the retaining collar portionare all integrally molded in one piece.

In an embodiment of the disclosure, the bottle closure assembly includesa cap portion, an elongated tether portion, and a retaining meansportion where the cap portion, the elongated tether portion, and theretaining means portion are all integrally molded in one piece.

In an embodiment of the disclosure, the bottle closure assembly includesa cap portion, an elongated tether portion, and a retaining collarportion where the cap portion, the elongated tether portion, and theretaining collar portion are all integrally molded in one piece.

In an embodiment of the disclosure, the bottle closure assembly includesa cap portion, a tether portion, and a retaining means portion where thecap portion, the tether portion, and the retaining means portion areseparately molded.

In an embodiment of the disclosure, the bottle closure assembly includesa cap portion, a tether portion, and a retaining collar portion wherethe cap portion, the tether portion, and the retaining collar portionare separately molded.

In an embodiment of the disclosure, the bottle closure assembly includesa cap portion, an elongated tether portion, and a retaining meansportion where the cap portion, the elongated tether portion, and theretaining means portion are separately molded.

In an embodiment of the disclosure, the bottle closure assembly includesa cap portion, an elongated tether portion, and a retaining collarportion where the cap portion, the elongated tether portion, and theretaining collar portion are separately molded.

In embodiments of the disclosure, when separately molded the capportion, the tether portion, and the retaining means portion may befixed together using any means known in the art. For example, the capportion, the tether portion, and the retaining means portion may beglued together, or welded together using applied heat, sonication orother methods known in the art for fusing plastic materials together.

In an embodiment of the disclosure, the bottle closure assembly includesa cap portion, a tether portion, and a retaining means portion where thecap portion, the tether portion, and the retaining means portion aremade from the same or different materials.

In an embodiment of the disclosure, the bottle closure assembly includesa cap portion, a tether portion, and a retaining collar portion wherethe cap portion, the tether portion, and the retaining collar portionare made from the same or different materials.

In an embodiment of the disclosure, the bottle closure assembly includesa cap portion, an elongated tether portion, and a retaining meansportion where the cap portion, the elongated tether portion, and theretaining means portion are made from the same or different materials.

In an embodiment of the disclosure, the bottle closure assembly includesa cap portion, an elongated tether portion, and a retaining collarportion where the cap portion, the elongated tether portion, and theretaining collar portion are made from the same or different materials.

In an embodiment of the present disclosure, the “tether portion” is ofsufficient length and/or has a design which allows removal of a “capportion” from a bottle opening while at the same time preventing theloss of the cap portion by maintaining a connection between the capportion and a bottle, container, or the like by forming a connectionbetween at least one point on the cap portion and at least one point ona “retaining means portion”.

In an embodiment of the present disclosure, the tether portion may be an“elongated tether portion”, where “elongated” means that the tetherportion will have at least one dimension (length) which is larger thanat least one other dimension (width or height/thickness) or vice versa.Or considered another way, “elongated” means that the tether has alength which is greater than its width and/or height/thickness.

In an embodiment of the present disclosure, the tether portion will havedimensions (e.g., width and/or height/thickness) which offer sufficientstrength to prevent facile cleavage or breakage of the tether whenplaced under stress or duress, such as for example when the tether issubjected to bending or flexional forces. For example, in an embodimentof the disclosure, the tether will have sufficient width and/orheight/thickness so as to prevent facile breakage of the tether whenmasticated.

In an embodiment of the present disclosure, the “elongated tetherportion” is of sufficient length and/or has a design which allowsremoval of a “cap portion” from a bottle opening while at the same timepreventing the loss of the cap portion by maintaining a connectionbetween the cap portion and a bottle, container or the like by forming aconnection between at least one point on the cap portion and at leastone point on a “retaining means portion”.

In embodiments of the disclosure, the retaining means portion may be a“retaining collar portion” which engages some portion of a bottle neckor an upper portion of a bottle, container, or the like.

In embodiments of the disclosure, the retaining means portion may be a“retaining collar portion” which irreversibly engages some portion of abottle neck, a spout, a spigot, a fitment on a pouch, or the like.

Alternatively, the retaining means portion may be a “retaining collarportion” which engages a bottle neck, or an upper portion of a bottle,container or the like.

In an embodiment of the disclosure, the retaining collar portion mayrotatably engage a bottle neck, or upper portion of a bottle, container,or the like.

In an embodiment of the disclosure, the retaining means portion is aretaining collar portion which is molded to irreversibly engage a bottleneck or an upper portion of a bottle, container, or the like.

In an embodiment of the disclosure, the retaining collar portion isannularly shaped or circularly shaped and can fit over and engage abottle neck or an upper portion of a bottle, container, or the like.

The cap portion may be a single contiguous piece, or it may itselfcomprise one or more cap portion structures.

The tether portion in the present disclosure need not serve as a hingedconnection between a cap portion or a closure portion and a retainingmeans portion (such as for example a retaining collar portion), and thetether portion need not comprise a hinged portion or area, but thetether portion may in some embodiments of the disclosure comprise ahinge and when present the hinge may be a so called “living hinge”.

In an embodiment of the disclosure, the elongated tether portion has alength which is sufficient to allow the cap portion of the bottleclosure assembly to swing or hang out of the way of a bottle opening,aperture, or the like so as not to interfere with the dispensation ofthe bottle contents, while at the same time tethering the cap portion toa bottle via the retaining means portion.

The cap portion may itself be a screw cap which threadingly engages athreaded system on a bottle neck, spigot, spout, valve, fitment on apouch, or the like. The cap portion may alternatively be a snap capwhich reversibly engages a bottle neck, spigot, spout, or the like. Thecap portion may also reversibly engage a retaining collar portion in asnap fitting or in a complementary arrangement of threaded structures.The cap portion may comprise a first cap portion and a second capportion, where the first cap portion engages the second cap portion in asnap fitting, and the second cap portion engages a bottle neck, or upperportion of a bottle in a reversible or irreversible manner. For example,a second cap portion may have a threaded structure which threadinglyengages a threaded system on a bottle neck. Alternatively, the secondcap portion may itself engage a bottle neck by any suitable type of snapfitting. The cap portion may also comprise more than two cap portions.

In an embodiment of the disclosure, the bottle closure assembly includesa cap portion adapted to close an opening in a bottle or the like bymaking a frictional engagement with the opening.

In an embodiment of the disclosure, the cap portion has internal threadswhich mate with external threads surrounding an opening in a bottle,such as on a bottle neck, spigot, or spout for example.

In an embodiment of the disclosure, the retaining collar portion isadapted to cooperate with a shoulder or a flange on the neck of a bottleor an upper portion of a bottle which is to be sealed by the capportion.

In an embodiment of the disclosure, the retaining collar portion isannularly or cylindrically shaped and fits onto the neck of a bottle andis coupled to the same, using any suitable coupling means, such as asnap fitting, or a threaded engagement. In an embodiment, the retainingcollar portion is molded to snap fit onto a bottle neck, bottleaperture, spigot, spout, or the like. In an embodiment, the retainingcollar portion may be threaded onto a bottle neck, bottle aperture,spigot, spout, or the like. In an embodiment the retaining collarportion may itself have an internal threading system which mates withexternal threads on a bottle neck, bottle aperture, spigot, spout or thelike. In an embodiment, the retaining collar portion is dimensioned tobe engaged beneath a flange or shoulder molded into a bottle neck or anupper portion of a bottle. For example, the retaining collar portion mayhave an annular radial dimension which prevents it from moving past anannular shoulder integrally molded into a bottle neck or into an upperportion of a bottle. In this case the annular outwardly extendingshoulder on a bottle neck or on an upper portion of a bottle acts as acamming surface which prevents movement of the retaining collar toward abottle opening. Such a shoulder on a bottle could for example have atapered outer annular edge which allows the retaining collar portion tobe slipped onto the bottle in an irreversible manner. In an embodimentof the disclosure, there may be outwardly extending annularly spacedbosses or the like on a bottle neck or an upper portion of a bottle,against which the retaining collar abuts to hold it on to a bottle neck,bottle aperture, spigot, spout, or the like. Persons skilled in the artwill appreciate that other means could be used to secure the retainingcollar portion to a bottle neck, the upper portion of a bottle, a spout,and the like.

In an embodiment of the disclosure, the elongated tether portionincludes a connecting strip having a first end connected to a least onepoint of the cap portion and a second end connected to at least onepoint of the retaining collar portion, a lower edge, and an upper edge,wherein when the cap portion is fitted on to a bottle opening, theconnecting strip at least partially encircles a bottle neck, spout, orthe like between the cap portion and the retaining collar portion, andwhere at least a portion of the upper edge of the connecting strip isfrangibly connected to a lower edge of the cap portion, and where atleast a portion of the lower edge of the connecting strip is frangiblyconnected to an upper edge of the retaining collar portion, and wherewhen the cap portion is removed from a bottle opening by breaking thefrangible connections between the cap portion, the connecting strip, andthe retaining collar portion, the cap portion remains secured toretaining collar portion and the bottle via the connecting strip.

In an embodiment, the elongated tether portion is a cylindricallyadapted connecting strip which at least partially encircles a bottleneck, spout, or the like and is located between the cap portion and theretaining collar portion prior to removal of the cap portion form abottle opening.

In an embodiment, the elongated tether portion has a first end which isconnected to at least one point on the cap portion and a second endwhich is connected to at least one point on the retaining collarportion.

In an embodiment, the cap portion, the elongated tether portion, and theretaining collar portion are integrally molded so that the elongatedtether portion has a first end which is connected to at least one pointon the cap portion and a second end which is connected to at least onepoint on the retaining collar.

In an embodiment, the cap portion, the elongated tether portion, and theretaining collar portion are integrally molded so that the elongatedtether portion has a first end which is connected to at least one pointon the cap portion and a second end which is connected to at least onepoint on the retaining collar portion, and wherein the elongated tetherportion has an upper edge and a lower edge, where at least a portion ofthe upper edge is frangibly connected to a lower edge of the capportion, and at least a portion of the lower edge is frangibly connectedto an upper edge of the retaining collar portion, the frangiblyconnected portions being breakable when the closure is removed from abottle opening.

In an embodiment of the disclosure, the frangible connections orfrangibly connected portions are regularly or irregularly spaced moldedsections (e.g., pins) having a dimension suitably small to allow facilebreakage.

Frangible connections or frangibly connected portions can also bethought of as defining a weakening line along which the elongatedtethering portion can be separated from the cap portion and theretaining collar portion. Such weakening lines can be generally definedas open sections alternating with bridging sections, where the bridgingsections have a dimension suitably small to allow facile breakage.Alternatively, the weakening lines are defined by lines of plastic whichhave been made thin enough to break under stress.

In an embodiment of the disclosure, a single piece of a molded plastichaving a suitable shape, is purposely weakened (by for example, regularor irregularly spaced cuts) along predetermined lines to define a capportion, an elongated tether portion, and a retaining collar portion,wherein the cap portion is shaped to reversibly engage and cover abottle opening, the retaining means portion is shaped to irreversiblyengage a bottle neck or an upper portion of a bottle, and where theelongated tether portion connects at least one point on the cap portionto at least one point on the retaining means portion.

In an embodiment of the disclosure, the bottle closure assembly includesan upper cap portion, an intermediate elongate tethering portion, and alower retaining collar portion, where the intermediate elongatetethering portion has a first end permanently connected to at least onepoint of the upper cap portion and a second end permanently connected toat least one point on the lower retaining collar portion, wherein theintermediate elongate tethering portion is partially joined to a lowerannular edge of the upper cap portion along a first peripheral weakeningline and the intermediate elongate tethering portion is partially joinedto an upper annular edge of the lower retaining collar portion along asecond peripheral weakening line, wherein removal of the upper capportion from a bottle separates the upper cap portion from theintermediate elongate tethering portion along the first peripheralweakening line and separates the lower retaining collar portion from theintermediate elongate tethering portion along the second weakening line,while maintaining a linkage between the upper cap portion and the lowerretaining collar portion through the intermediate elongate tetheringportion.

In an embodiment of the disclosure, and with reference to FIGS. 1A-1C,the bottle closure assembly includes: an upper cap portion, 1dimensioned to reversibly cover and close a bottle opening, a lowerretaining collar portion, 10 dimensioned to irreversibly engage a bottleneck, or an upper portion of a bottle, and an elongated tether portion,5 being dimensioned as a strip which at least partially encircles abottle neck between the upper cap portion and the lower retaining collarportion, the strip including a first end, a second end, an upper edge,and a lower edge, the upper edge of which is in part contiguous with theupper cap portion, the lower edge of which is in part contiguous withthe lower retaining collar portion, whereby removal of the upper capportion from a bottle (by for example rotation about a threaded systemon the bottle neck) separates the elongated tether portion from theupper cap portion and the lower retaining collar portion, while at thesame leaving the upper cap portion attached to the lower retainingcollar via the elongated tether portion.

In an embodiment of the disclosure, and with reference to FIGS. 2A and2B, the bottle closure assembly includes: an upper cap portion, 1dimensioned to reversibly cover and close a bottle opening, 2 a lowerretaining collar portion, 10 dimensioned to irreversibly engage a bottleneck, 3 or an upper portion of a bottle, and an elongated tetherportion, 5 being dimensioned as a strip which at least partiallyencircles a bottle neck between the upper cap portion and the lowerretaining collar portion, the strip including a first end, 6 a secondend, 7 an upper edge, 11 and a lower edge, 12, the upper edge of whichis in part frangibly attached, 8 to the upper cap portion, and in partcontiguous with the upper cap portion, the lower edge of which is inpart frangibly attached, 9 to the lower retaining collar portion and inpart contiguous with the lower retaining collar portion, whereby removalof the upper cap portion from a bottle will rupture the frangibleattachments while leaving the upper cap portion attached to the lowerretaining collar portion via the elongated tether portion. In anembodiment and with reference to FIG. 2B, the bottle opening may haveperipheral threads, 15 which engage threads on the inside of the capportion.

In an embodiment of the disclosure, and with reference to FIGS. 3A-3C,the bottle closure assembly includes: an opening, 2, an upper capportion, 1 dimensioned to reversibly cover and close a bottle opening, alower retaining collar portion, 10 dimensioned to irreversibly engage abottle neck, 3 or an upper portion of a bottle, and an elongated tetherportion, 5 being dimensioned as a strip which at least partiallyencircles a bottle neck between the upper cap portion and the lowerretaining collar portion, the strip having a first end, 6 a second end,7 an upper edge, and a lower edge, the upper edge of which is in partfrangibly attached to the upper cap portion by frangible elements, 20(such as for example breakable pins), and in part contiguous with theupper cap portion, the lower edge of which is in part frangibly attachedto the lower retaining collar portion by frangible elements, 20 (such asfor example breakable pins) and in part contiguous with the lowerretaining collar portion, whereby removal of the upper cap portion froma bottle opening will rupture the frangible attachments while leavingthe upper cap portion attached to the lower retaining collar portion viathe elongated tether portion, 5. In an embodiment and with reference toFIG. 3B, the bottle neck and opening may have peripheral threads, 15which engage threads on the inside of the cap portion.

In an embodiment of the disclosure, and with reference to FIGS. 4A-4C,the bottle closure assembly includes a cap portion, 1, an elongatedtether portion, 5, and a retaining collar portion, 10.

In an embodiment of the disclosure, and with reference to FIGS. 5A and5B, the bottle closure assembly includes: a cap portion, 1 an elongatedtether portion, 5 and a retaining means portion, 10 the cap portionbeing molded to reversibly engage and cover a bottle opening, theretaining means portion being molded to irreversibly engage a bottleneck or an upper portion of a bottle, 18 and the elongated tetherportion being molded to connect at least one point on the cap portion toat least one point on the retaining means portion, the cap portion andthe retaining collar portion extending coaxially with each other, theelongated tethering portion including a tabbed tether strip which isintegrally formed with and secured at its respective ends (6 and 7) tothe cap portion and the retaining collar portion, the tether strip beingjoined to the cap portion and the retaining collar along a preselectedlength of the tether strip to be manually separated from the cap portionand the retaining collar portion by frangible elements, 20 of apreselected thickness to permit the tether strip to be manuallyseparated from the cap portion and the retaining collar portion alongthe pre-selected length, the tether strip being of such length so as topermit the cap portion to be removed from a bottle opening while at thesame remaining attached to the bottle via the tethering strip and theretaining collar. In an embodiment and as shown in FIG. 5B, a capportion may have a circular top wall, 16 and a descending annular sidewall 17.

In an embodiment of the disclosure, the bottle closure assemblyincludes: a cap portion having a top wall and a side wall, an elongatedtether portion, and a retaining collar portion, the cap portion beingmolded to reversibly engage and cover a bottle opening, the retainingcollar portion being annular and being molded to irreversibly engage aridge or flange on a bottle neck or on an upper portion of a bottle, andthe elongated tether portion being integrally molded with the capportion and the retaining collar portion to connect at least one pointon the cap side wall to at least one point on the retaining collarportion, wherein the elongated tether portion runs between the cap sidewall and the retaining collar portion along the circumference of the capportion when the cap portion is on a bottle and the elongated tetherportion connects at least one point on the cap side wall to at least onepoint on the retaining collar portion when the cap portion is removedfrom a bottle.

In an embodiment of the disclosure, and with reference to FIGS. 6A and6B, the bottle closure assembly includes an opening, 2, an upper capportion, 1 an intermediate elongate tethering portion, 5 and a lowerretaining collar portion, 10 where the intermediate elongate tetheringportion has a first end permanently connected to at least one point ofthe upper cap portion and a second end permanently connected to at leastone point on the lower retaining collar portion, wherein theintermediate elongate tethering portion is partially joined to a lowerannular edge of the upper cap portion along a first peripheral weakeningline defined by perforations, 25 and the intermediate elongate tetheringportion is partially joined to an upper annular edge of the lowerretaining collar portion along a second peripheral weakening linedefined by perforations, 25 wherein removal of the upper cap portionfrom a bottle separates the upper cap portion from the tethering portionalong the first peripheral weakening line and separates the lowerretaining collar portion from the tethering portion along the secondweakening line, while maintaining a linkage between the upper capportion and the lower retaining collar portion through the intermediateelongated tethering portion.

In an embodiment of the disclosure, and with reference to FIGS. 6A and6B, a bottle neck 3, may have an annular groove 28, which presents aflange onto which the cap portion, 1 may reversibly engage in a snap fitarrangement. In an embodiment and with reference to FIGS. 6A and 6B abottle neck may have an outwardly extended annular flange, 29 whichprevents a retaining collar portion, 10 from being removed from a bottleneck.

In an embodiment of the disclosure, and with reference to FIGS. 7A and7B, the bottle closure assembly includes a cap portion, 1, an elongatedtether portion, 5, and a retaining collar portion, 10. The elongatedtether portion connects at least one point of the cap portion at a firstend, 6 to at least one point of the retaining collar portion at a secondend, 7. The elongated tether portion may be further joined to the capportion along a frangible connection 8. The elongated tether portion maybe further joined to the retaining collar portion along a frangibleconnection 9. Separation of the cap portion from the elongated tetherportion along a frangible connection 8 along with separation of theretaining collar portion from the elongated tether portion along afrangible connection 9, allows removal of the cap portion from a bottleopening while at the same time securing it to the bottle via theelongated tether portion and the retaining collar portion.

In an embodiment of the disclosure, the bottle closure assemblyincludes: a cap portion, the cap portion being dimensioned to cover andclose a bottle opening, a retaining collar portion, and an elongatedtether portion which forms an elastic connection between at least onepoint on the cap portion and at least one point on the retaining collarportion.

In an embodiment of the disclosure, the retaining means portion isintegrally molded into a bottle, container, or the like.

In an embodiment of the disclosure, the retaining collar portion isintegrally molded into a bottle, container, or the like.

In an embodiment of the disclosure, the tether portion fixes the capportion to the retaining collar portion which remains secured to thebottle, making it difficult to separate the cap portion from the bottle,thereby preventing its loss, while at the same time allowing rotation ofthe cap portion for facile removal and replacement of the same from andonto a bottle opening.

In the present disclosure, the bottle closure assembly is made in partor in full using a polyethylene composition including: 1) 10 to 70 wt. %of a first ethylene copolymer having a melt index I₂, of 10 g/10 min orless; and a density of from 0.920 to 0.960 g/cm³; and 2) 90 to 30 wt. %of a second ethylene copolymer having a melt index I₂, of at least 50g/10 min; and a density higher than the density of the first ethylenecopolymer, but less than 0.970 g/cm³; wherein the ratio (SCB1/SCB2) ofthe number of short chain branches per thousand carbon atoms in thefirst ethylene copolymer (SCB1) to the number of short chain branchesper thousand carbon atoms in the second ethylene copolymer (SCB2) isgreater than 0.5.

In an embodiment of the disclosure, the cap portion, optionally thetether portion, and optionally the retaining collar portion are madefrom a polyethylene composition including: 1) 10 to 70 wt. % of a firstethylene copolymer having a melt index I₂, of 10 g/10 min or less; and adensity of from 0.920 to 0.960 g/cm³; and 2) 90 to 30 wt. % of a secondethylene copolymer having a melt index I₂, of at least 50 g/10 min; anda density higher than the density of the first ethylene copolymer, butless than 0.970 g/cm³; wherein the ratio (SCB1/SCB2) of the number ofshort chain branches per thousand carbon atoms in the first ethylenecopolymer (SCB1) to the number of short chain branches per thousandcarbon atoms in the second ethylene copolymer (SCB2) is greater than0.5.

In an embodiment of the disclosure, the cap portion, the tether portion,and the retaining collar portion are all integrally molded from apolyethylene composition including: 1) 10 to 70 wt. % of a firstethylene copolymer having a melt index I₂, of 10 g/10 min or less; and adensity of from 0.920 to 0.960 g/cm³; and 2) 90 to 30 wt. % of a secondethylene copolymer having a melt index I₂, of at least 50 g/10 min; anda density higher than the density of the first ethylene copolymer, butless than 0.970 g/cm³; wherein the ratio (SCB1/SCB2) of the number ofshort chain branches per thousand carbon atoms in the first ethylenecopolymer (SCB1) to the number of short chain branches per thousandcarbon atoms in the second ethylene copolymer (SCB2) is greater than0.5.

Further polyethylene compositions suitable for use in the manufacture ofpart or all of the bottle closure assembly discussed above are disclosedin for example U.S. Pat. Nos. 8,022,143; 8,962,755; 9,074,082;9,371,442; 9,505,893; 9,475,927; 9,637,628; 9,758,653; 9,783,663; and9,783,664 all of which are incorporated, in their entirety, herein.

Suitable polyethylene compositions for use in the manufacture of part orall of the bottle closure assembly are described in more detail below.

The polyethylene compositions are composed of at least two ethylenecopolymer components: a first ethylene copolymer and a second ethylenecopolymer.

By the term “ethylene copolymer”, it is meant that the copolymerincludes both ethylene and at least one alpha-olefin comonomer.

The terms “homogeneous” or “homogeneously branched polymer” as usedherein define homogeneously branched polyethylene which has a relativelynarrow composition distribution, as indicated by a relatively highcomposition distribution breadth index (CDBI₅₀). That is, the comonomeris randomly distributed within a given polymer chain and a substantialportion of the polymer chains have same ethylene/comonomer ratio. It iswell known that metallocene catalysts and other so called “single sitecatalysts” incorporate comonomer more evenly than traditionalZiegler-Natta catalysts when used for catalytic ethylenecopolymerization with alpha olefins. This fact is often demonstrated bymeasuring the composition distribution breadth index (CDBI₅₀) forcorresponding ethylene copolymers. The composition distribution of apolymer can be characterized by the short chain distribution index(SCDI) or composition distribution breadth index (CDBI₅₀). Thedefinition of composition distribution breadth index (CDBI₅₀) can befound in PCT Application Publication No. WO 93/03093 and U.S. Pat. No.5,206,075. The CDBI₅₀ is conveniently determined using techniques whichisolate polymer fractions based on their solubility (and hence theircomonomer content). For example, temperature rising elutionfractionation (TREF) as described by Wild et al. J. Poly. Sci., Poly.Phys. Ed. Vol. 20, p 441, 1982 or in U.S. Pat. No. 4,798,081 can beemployed. From the weight fraction versus composition distributioncurve, the CDBI₅₀ is determined by establishing the weight percentage ofa copolymer sample that has a comonomer content within 50% of the mediancomonomer content on each side of the median. Generally, Ziegler-Nattacatalysts produce ethylene copolymers with a CDBI₅₀ of less than about50 weight %, or less than about 55 weight %, consistent with aheterogeneously branched copolymer. In contrast, metallocenes and othersingle site catalysts will most often produce ethylene copolymers havinga CDBI₅₀ of greater than about 55 weight %, or greater than about 60weight %, consistent with a homogeneously branched copolymer.

In one embodiment of the disclosure, the polyethylene composition willcomprise at least a first ethylene copolymer and at least a secondethylene copolymer which is different from the first ethylene polymer.

The First Ethylene Copolymer

In an embodiment of the disclosure, the first ethylene copolymer of thepolyethylene composition has a density of from about 0.930 g/cm³ toabout 0.960 g/cm³; a melt index, 12, of more than 0.1 g/10 min; amolecular weight distribution, M_(w)/M_(n), of below about 3.0 and aweight average molecular weight M_(w), that is greater than the M_(w) ofthe second ethylene copolymer. In one embodiment, the weight averagemolecular weight M_(w), of the first ethylene copolymer is at least50,000 g/mol.

By the term “ethylene copolymer” it is meant that the copolymer includesboth polymerized ethylene and at least one polymerized alpha-olefincomonomer, with polymerized ethylene being the majority species.

In an embodiment of the disclosure, the first ethylene copolymer is madewith a single site catalyst, such as, for example, a phosphiniminecatalyst.

The comonomer (i.e., alpha-olefin) content in the first ethylenecopolymer can be from about 0.05 to about 3.0 mole percent (mol %) asmeasured by ¹³C NMR, or FTIR or GPC-FTIR methods, or as calculated froma reactor model (see the Examples section). The comonomer is one or moresuitable alpha olefin, which include, but are not limited to, 1-butene,1-hexene, 1-octene, and the like. In one embodiment the alpha-olefin is1-octene.

The short chain branching in the first ethylene copolymer can be fromabout 0.25 to about 15 short chain branches per thousand carbon atoms(SCB1/1000 Cs). In further embodiments of the disclosure, the shortchain branching in the first ethylene copolymer can be from 0.25 to 10,or from 0.25 to 7.5, or from 0.25 to 5, or from 0.25 to 3 branches perthousand carbon atoms (SCB1/1000 Cs). The short chain branching is thebranching due to the presence of alpha-olefin comonomer in the ethylenecopolymer and will for example have two carbon atoms for a 1-butenecomonomer, or four carbon atoms for a 1-hexene comonomer, or six carbonatoms for a 1-octene comonomer, etc. The comonomer is one or moresuitable alpha-olefin, which include, but are not limited to, 1-butene,1-hexene, 1-octene, and the like. In one embodiment, the alpha olefin is1-octene.

In an embodiment of the disclosure, the comonomer content in the firstethylene copolymer is greater than comonomer content of the secondethylene copolymer (as reported, for example, in mol %).

In an embodiment of the disclosure, the amount of short chain branchingin the first ethylene copolymer is greater than the amount of shortchain branching in the second ethylene copolymer (as reported in shortchain branches, SCB per thousand carbons in the polymer backbone, 1000Cs).

In some embodiments of the disclosure, the melt index, 12, of the firstethylene copolymer can be 10 g/10 min or less.

In some embodiments of the disclosure, the melt index, 12, of the firstethylene copolymer can be from 0.1 to 10 g/10 min and including narrowerranges within this range and any numbers encompassed by these ranges.For example, the melt index I₂ of the first ethylene composition can befrom above 0.1 to below 10 g/10 min, or can be from 0.1 to 7.5 g/10 min,or from 0.1 to 5.0 g/10 min, or from 0.1 to 3.0 g/10 min, or from 0.1 to2.5 g/10 min, or from 0.1 to 1.0 g/10 min.

In an embodiment of the disclosure, the first ethylene copolymer has aweight average molecular weight M_(w) of from about 50,000 to about225,000 g/mol including narrower ranges and any numbers encompassed bythese ranges. For example, in another embodiment of the disclosure, thefirst ethylene copolymer has a weight average molecular weight M_(w) offrom about 75,000 to about 200,000. In further embodiments of thedisclosure, the first ethylene copolymer has a weight average molecularweight M_(w) of from about 75,000 to about 175,000, or from about 85,000to about 150,000, or from about 100,000 to about 150,000.

In some embodiments, the density of the first ethylene copolymerdisclosed herein is from 0.920 to 0.960 g/cm³ or can be a narrower rangewithin this range and any numbers encompassed by these ranges.

In some embodiments, the density of the first ethylene copolymerdisclosed herein is from 0.930 to 0.960 g/cm³ or can be a narrower rangewithin this range and any numbers encompassed by these ranges. Forexample, in further embodiments of the disclosure, the density of thefirst ethylene copolymer can be from 0.936 to 0.960 g/cm³, or can befrom 0.938 to 0.960 g/cm³, or from 0.936 to 0.952 g/cm³, or from 0.938to 0.952 g/cm³, or from 0.936 to 0.950 g/cm³, or from 0.938 to 0.950g/cm³, or from 0.936 to 0.947 g/cm³, or from 0.938 to 0.947 g/cm³, orfrom 0.936 to 0.945 g/cm³, or from 0.938 to 0.945 g/cm³.

In embodiments of the disclosure, the first ethylene copolymer has amolecular weight distribution M_(w)/M_(n) of <3.0, or ≤2.7, or <2.7, or≤2.5, or <2.5, or ≤2.3, or from 1.8 to 2.3.

In an embodiment of the disclosure, the first ethylene copolymer of thepolyethylene composition is produced with a single site catalyst and hasa weight average molecular weight M_(w), of at least 50,000 g/mol; amolecular weight distribution, M_(w)/M_(n), of less than 3.0 and adensity of from 0.936 to 0.950 g/cm³.

In an embodiment of the disclosure, a single site catalyst which givesan ethylene copolymer having a CDBI(50) of at least 65% by weight, or atleast 70%, or at least 75%, or at least 80%, or at least 85%, duringsolution phase polymerization in a single reactor, is used in thepreparation of the first ethylene copolymer.

In an embodiment of the present disclosure, the first ethylene copolymeris an ethylene copolymer which has a CDBI(50) of greater than about 60%by weight, or greater than about 65%, or greater than about 70%, orgreater than about 75%, or greater than about 80%, or greater than about85%.

In an embodiment of the disclosure, the first ethylene copolymer cancomprise from about 10 to about 90 weight percent (wt. %) of the totalweight of the first and second ethylene copolymers. In an embodiment ofthe disclosure, the first ethylene copolymer can comprise from about 10to about 80 weight percent (wt. %) of the total weight of the first andsecond ethylene copolymers. In an embodiment of the disclosure, thefirst ethylene copolymer can comprise from about 10 to about 70 weightpercent (wt. %) of the total weight of the first and second ethylenecopolymers. In an embodiment of the disclosure, the first ethylenecopolymer includes from 20 to about 60 weight percent (wt. %) of thetotal weight of the first and second ethylene copolymers. In anembodiment of the disclosure, the first ethylene copolymer includes fromabout 25 to about 60 weight percent (wt. %) of the total weight of thefirst and second ethylene copolymers. In an embodiment of thedisclosure, the first ethylene copolymer includes from about 30 to about60 weight percent (wt. %) of the total weight of the first and secondethylene copolymers. In an embodiment of the disclosure, the firstethylene copolymer includes from about 40 to about 50 weight percent(wt. %) of the total weight of the first and second ethylene copolymers.

The Second Ethylene Copolymer

In an embodiment of the disclosure, the second ethylene copolymer has adensity which is higher than the density of the first ethylenecopolymer.

In an embodiment of the disclosure, the second ethylene copolymer of thepolyethylene composition of the current disclosure has a density below0.967 g/cm³ but which is higher than the density of the first ethylenecopolymer; a melt index I₂, of from about 50 to 10,000 g/10 min; amolecular weight distribution, M_(w)/M_(n), of below about 3.0 and aweight average molecular weight M_(w) that is less than the M_(w) of thefirst ethylene copolymer. In one embodiment, the weight averagemolecular weight, M_(w) of the second ethylene copolymer will be below45,000 g/mole.

In an embodiment of the disclosure, the second ethylene copolymer ismade with a single site catalyst, such as for example a phosphiniminecatalyst.

The comonomer content in the second ethylene copolymer can be from about0.05 to about 3 mol % as measured by ¹³C NMR, or FTIR or GPC-FTIRmethods, or as calculated from a reactor model (see Examples section).The comonomer is one or more suitable alpha olefins, which include, butare not limited to, 1-butene, 1-hexene, 1-octene, and the like. In oneembodiment the alpha olefin is 1-octene.

The short chain branching in the second ethylene copolymer can be fromabout 0.25 to about 15 short chain branches per thousand carbon atoms(SCB1/1000 Cs). In further embodiments of the disclosure, the shortchain branching in the first ethylene copolymer can be from 0.10 to 10,or from 0.15 to 10, or from 0.20 to 10, or from 0.25 to 10, or from 0.25to 7.5, or from 0.25 to 5, or from 0.25 to 3, or from 0.10 to 3, or from0.15 to 3, or from 0.20 to 3 branches per thousand carbon atoms(SCB1/1000 Cs). The short chain branching is the branching due to thepresence of alpha-olefin comonomer in the ethylene copolymer and willfor example have two carbon atoms for a 1-butene comonomer, or fourcarbon atoms for a 1-hexene comonomer, or six carbon atoms for a1-octene comonomer, etc. The comonomer is one or more suitable alphaolefin. Examples of alpha olefins include, but are not limited to1-butene, 1-hexene, 1-octene, and the like. In one embodiment the alphaolefin is 1-octene.

In an embodiment of the disclosure, the comonomer content in the secondethylene copolymer is less than the comonomer content of the firstethylene copolymer (as reported for example in mol %).

In an embodiment of the disclosure, the amount of short chain branchingin the second ethylene copolymer is less than the amount of short chainbranching in the first ethylene copolymer (as reported in short chainbranches, SCB per thousand carbons in the polymer backbone, 1000 Cs).

In some embodiments, the density of the second ethylene copolymer isless than 0.970 g/cm³.

In some embodiments the density of the second ethylene copolymer is lessthan 0.967 g/cm³. In another embodiment of the disclosure, the densityof the second ethylene copolymer is less than 0.966 g/cm³. In anotherembodiment of the disclosure, the density of the second ethylenecopolymer is less than 0.965 g/cm³. In another embodiment of thedisclosure, the density of the second ethylene copolymer is less than0.964 g/cm³. In an embodiment of the disclosure, the density of thesecond ethylene copolymer is from 0.952 to 0.967 g/cm³ or can be anarrower range within this range, including all the number encompassedwithin these ranges. In further embodiments of the disclosure, thedensity of the second ethylene copolymer is from 0.950 to 0.965 g/cm³,or from 0.952 to 0.965 g/cm³, or from 0.950 to below 0.965 g/cm³, orfrom 0.952 to below 0.965 g/cm³; or from 0.950 to 0.964 g/cm³, or from0.952 to 0.964 g/cm³, or from 0.954 to 0.964 g/cm³.

In some embodiments of the disclosure, the density of the secondethylene copolymer is higher than the density of the first ethylenecopolymer, but is less than 0.970 g/cm³.

In some embodiments, the second ethylene copolymer has a density whichis higher than the density of the first ethylene copolymer, but lessthan about 0.037 g/cm³ higher than the density of the first ethylenecopolymer. In an embodiment of the disclosure, the second ethylenecopolymer has a density which is higher than the density of the firstethylene copolymer, but less than about 0.035 g/cm³ higher than thedensity of the first ethylene copolymer. In another embodiment of thedisclosure, the second ethylene copolymer has a density which is higherthan the density of the first ethylene copolymer, but less than about0.030 g/cm³ higher than the density of the first ethylene copolymer. Instill another embodiment of the disclosure, the second ethylenecopolymer has a density which is higher than the density of the firstethylene copolymer, but less than about 0.027 g/cm³ higher than thedensity of the first ethylene copolymer. In still another embodiment ofthe disclosure, the second ethylene copolymer has a density which ishigher than the density of the first ethylene copolymer, but less thanabout 0.025 g/cm³ higher than the density of the first ethylenecopolymer.

In an embodiment of the disclosure, the second ethylene copolymer has aweight average molecular weight M_(w) of less than 45,000 g/mol. Inanother embodiment of the disclosure, the second ethylene copolymer hasa weight average molecular weight M_(w) of from about 7,500 to about40,000. In further embodiments of the disclosure, the second ethylenecopolymer has a weight average molecular weight M_(w) of from about9,000 to about 35,000, or from about 10,000 to about 30,000, or fromabout 10,000 to 25,000.

In embodiments of the disclosure, the second ethylene copolymer has amolecular weight distribution (M_(w)/M_(n)) of <3.0, or ≤2.7, or <2.7,or ≤2.5, or <2.5, or ≤2.3, or from 1.8 to 2.3.

In an embodiment of the disclosure, the melt index I₂ of the secondethylene copolymer can be at least 50 g/10 min.

In an embodiment of the disclosure, the melt index I₂ of the secondethylene copolymer can be from 50 to 10,000 g/10 min. In anotherembodiment of the disclosure, the melt index I₂ of the second ethylenecopolymer can be from 100 to 5,000 g/10 min. In another embodiment ofthe disclosure, the melt index I₂ of the second ethylene copolymer canbe from 50 to 3,500 g/10 min. In another embodiment of the disclosure,the melt index I₂ of the second ethylene copolymer can be from 100 to10,000 g/10 min. In yet another embodiment of the disclosure, the meltindex I₂ of the second ethylene copolymer can be from 1000 to 7000 g/10min. In yet another embodiment of the disclosure, the melt index I₂ ofthe second ethylene copolymer can be from 1200 to 10,000 g/10 min. Inyet another embodiment of the disclosure, the melt index I₂ of thesecond ethylene copolymer can be from 1200 to 7,000 g/10 min. In yetanother embodiment of the disclosure, the melt index I₂ of the secondethylene copolymer can be greater than 1200, but less than 5000 g/10min. In still yet another embodiment of the disclosure, the melt indexI₂ of the second ethylene copolymer can be greater than 1000, but lessthan 3000 g/10 min. In still yet another embodiment of the disclosure,the melt index I₂ of the second ethylene copolymer can be greater than500, but less than 3000 g/10 min. In still yet another embodiment of thedisclosure, the melt index I₂ of the second ethylene copolymer can begreater than 250, but less than 2700 g/10 min. In still yet anotherembodiment of the disclosure, the melt index I₂ of the second ethylenecopolymer can be greater than 150, but less than 2700 g/10 min.

In an embodiment of the disclosure, the melt index I₂ of the secondethylene copolymer is greater than 100 g/10 min. In an embodiment of thedisclosure, the melt index I₂ of the second ethylene copolymer isgreater than 200 g/10 min. In an embodiment of the disclosure, the meltindex I₂ of the second ethylene copolymer is greater than 500 g/10 min.In an embodiment of the disclosure, the melt index I₂ of the secondethylene copolymer is greater than 1000 g/10 min. In an embodiment ofthe disclosure, the melt index I₂ of the second ethylene copolymer isgreater than 1200 g/10 min. In an embodiment of the disclosure, the meltindex I₂ of the second ethylene copolymer is greater than 1500 g/10 min.

In an embodiment of the disclosure, the second ethylene copolymer of thepolyethylene composition is made with a single site catalyst and has aweight average molecular weight, M_(w), of at most 45,000; a molecularweight distribution, M_(w)/M_(n), of less than 3.0 and a density higherthan the density of the first ethylene copolymer, but less than 0.967g/cm³.

In an embodiment of the disclosure, a single site catalyst which givesan ethylene copolymer having a CDBI(50) of at least 65% by weight, or atleast 70%, or at least 75%, or at least 80%, or at least 85%, duringsolution phase polymerization in a single reactor, is used in thepreparation of the second ethylene copolymer.

In an embodiment of the present disclosure, the second ethylenecopolymer has a CDBI(50) of greater than about 60% by weight, or greaterthan about 65%, or greater than about 70%, or greater than about 75%, orgreater than about 80%, or greater than about 85%.

In an embodiment of the disclosure, the second ethylene copolymer cancomprise from about 90 to about 10 wt. % of the total weight of thefirst and second ethylene copolymers. In an embodiment of thedisclosure, the second ethylene copolymer can comprise from about 90 toabout 20 wt. % of the total weight of the first and second ethylenecopolymers. In an embodiment of the disclosure, the second ethylenecopolymer can comprise from about 90 to about 30 wt. % of the totalweight of the first and second ethylene copolymers. In an embodiment ofthe disclosure, the second ethylene copolymer includes from about 80 toabout 40 wt. % of the total weight of the first and second ethylenecopolymers. In an embodiment of the disclosure, the second ethylenecopolymer includes from about 75 to about 40 wt. % of the total weightof the first and second ethylene copolymers. In an embodiment of thedisclosure, the second ethylene copolymer includes from about 70 toabout 40 wt. % of the total weight of the first and second ethylenecopolymers. In an embodiment of the disclosure, the second ethylenecopolymer includes from about 60 to about 50 wt. % of the total weightof the first and second ethylene copolymers.

In embodiments of the disclosure, the melt index I₂ of the secondethylene copolymer is at least 10 times, or at least 50 times, or atleast 100 times, or at least 1,000 times the melt index I₂ of the firstethylene copolymer.

The Polyethylene Composition

In some embodiments of the disclosure, the polyethylene composition hasa unimodal, broad unimodal, bimodal or multimodal molecular weightdistribution as determined by gel permeation chromatography.

In an embodiment of the disclosure, the polyethylene composition thatincludes a first ethylene copolymer and a second ethylene copolymer (asdefined above) will have a ratio (SCB1/SCB2) of the number of shortchain branches per thousand carbon atoms in the first ethylene copolymer(i.e., SCB1) to the number of short chain branches per thousand carbonatoms in the second ethylene copolymer (i.e., SCB2) of greater than 0.5(i.e., SCB1/SCB2>0.5). In an embodiment of the disclosure, thepolyethylene composition that includes a first ethylene copolymer and asecond ethylene copolymer (as defined above) will have a ratio(SCB1/SCB2) of the number of short chain branches per thousand carbonatoms in the first ethylene copolymer (i.e., SCB1) to the number ofshort chain branches per thousand carbon atoms in the second ethylenecopolymer (i.e., SCB2) of greater than 1.0 (i.e., SCB1/SCB2>1.0).

In further embodiments of the disclosure, the ratio of the short chainbranching in the first ethylene copolymer (SCB1) to the short chainbranching in the second ethylene copolymer (SCB2) is at least 1.25. Instill another embodiment of the disclosure, the ratio of the short chainbranching in the first ethylene copolymer (SCB1) to the short chainbranching in the second ethylene copolymer (SCB2) is at least 1.5.

In embodiments of the disclosure, the ratio (SCB1/SCB2) of the shortchain branching in the first ethylene copolymer (SCB1) to the shortchain branching in the second ethylene copolymer (SCB2) will be fromgreater than 1.0 to about 12.0, or from greater than 1.0 to about 10, orfrom greater than 1.0 to about 7.0, or from greater than 1.0 to about5.0, or from greater than 1.0 to about 3.0.

In an embodiment of the disclosure, the polyethylene composition isbimodal as determined by GPC.

A bimodal or multimodal polyethylene composition can be identified byusing gel permeation chromatography (GPC). A GPC chromatograph mayexhibit two or more component ethylene copolymers, where the number ofcomponent ethylene copolymers corresponds to the number of discerniblepeaks. One or more component ethylene copolymers may also exist as ahump, shoulder or tail relative to the molecular weight distribution ofthe other ethylene copolymer component. By the phrase “bimodal asdetermined by GPC”, it is meant that in addition to a first peak, therewill be a secondary peak or shoulder which represents a higher or lowermolecular weight component (i.e., the molecular weight distribution, canbe said to have two maxima in a molecular weight distribution curve).Alternatively, the phrase “bimodal as determined by GPC” connotes thepresence of two maxima in a molecular weight distribution curvegenerated according to the method of ASTM D6474-99.

In an embodiment of the present disclosure, the polyethylene compositionhas a density of greater than or equal to 0.950 g/cm³, as measuredaccording to ASTM D792; a melt index I₂, of from about 2 to about 22g/10 min, as measured according to ASTM D1238 (when conducted at 190°C., using a 2.16 kg weight); a molecular weight distribution,M_(w)/M_(n), of from about 2 to about 7, a Z-average molecular weightM_(z), of less than about 300,000; a stress exponent of less than 1.40;and an ESCR Condition B at 100% IGEPAL® CO-630 of at least about 3hours.

In embodiments of the disclosure, the polyethylene composition has acomonomer content of less than about 0.75 mol %, or less than about 0.70mol %, or less than about 0.65 mol %, or less than about 0.60 mol %, orless than about 0.55 mol %, or less than about 0.50 mol % as measured byFTIR or ¹³C NMR methods, where the comonomer is one or more suitablealpha olefins, which include, but are not limited to, 1-butene,1-hexene, 1-octene, and the like. In one embodiment the alpha olefin is1-octene.

In some embodiments the polyethylene composition has a density of atleast 0.950 g/cm³. In further embodiments of the disclosure, thepolyethylene composition has a density of >0.952 g/cm³, or >0.953 g/cm³,or >0.955 g/cm³.

In an embodiment of the disclosure, the polyethylene composition has adensity in the range of 0.950 to 0.970 g/cm³. In an embodiment of thecurrent disclosure, the polyethylene composition has a density in therange of 0.950 to 0.965 g/cm³.

In an embodiment of the disclosure, the polyethylene composition has adensity in the range of 0.950 to 0.962 g/cm³.

In an embodiment of the disclosure, the polyethylene composition has adensity in the range of 0.952 to 0.960 g/cm³.

In an embodiment of the disclosure, the polyethylene composition has adensity in the range of 0.950 to 0.960 g/cm³.

In an embodiment of the disclosure, the polyethylene composition has adensity in the range of 0.950 to 0.959 g/cm³.

In an embodiment of the disclosure, the polyethylene composition has adensity in the range of 0.951 to 0.957 g/cm³.

In an embodiment of the disclosure, the polyethylene composition has adensity in the range of 0.952 to 0.957 g/cm³.

In an embodiment of the disclosure, the polyethylene composition has amelt index I₂, of from 0.5 to 35 g/10 min according to ASTM D1238 (whenconducted at 190° C., using a 2.16 kg weight) and including narrowerranges within this range and all numbers encompassed by these ranges.

In an embodiment of the disclosure, the polyethylene composition has amelt index I₂, of from 2 to 22 g/10 min according to ASTM D1238 (whenconducted at 190° C., using a 2.16 kg weight) and including narrowerranges within this range and all numbers encompassed by these ranges.For example, in further embodiments of the disclosure, the polyethylenecomposition has a melt index I₂, of greater than 2, but less than 22g/10 min, or from 2 to 15.0 g/10 min, or from 3 to 12.5 g/10 min, orfrom 4 to 12.5 g/10 min, or from greater than 4 to less than 20 g/10min, or from 4.5 to 10 g/10 min, or from 5 to 20 g/10 min, or fromgreater than 5.0 to less than 20 g/10 min, or from 3 to 15.0 g/10 min,or from 6.0 to 12.0 g/10 min, or from 6.0 to about 10.0 g/10 min, orfrom about 5.0 to about 12.0 g/10 min, or from more than about 5.0 toless than about 10.0 g 10/min.

In an embodiment of the disclosure, the polyethylene composition has amelt index I₂, of ≤10.0 g/10 min, or less than 10 g/10 min, or fromgreater than 4.5 to 10 g/10 min, or from 4.0 to 10 g/10 min, or from 3.0to 10 g/10 min, or from 2.0 to 10 g/10 min, or from 1.0 to 10.0 g/10 minaccording to ASTM D1238 (when conducted at 190° C., using a 2.16 kgweight) and including narrower ranges within this range and all numbersencompassed by these ranges.

In an embodiment of the disclosure, the polyethylene composition has a“medium load” melt index, 15, of at least about 2.5 g/10 min accordingto ASTM D1238 (when conducted at 190° C., using a 5 kg weight). Inanother embodiment of the disclosure, the polyethylene composition has amedium load melt index, 15, of greater than about 5.0 g/10 min, asmeasured according to ASTM D1238 (when conducted at 190° C., using a 5kg weight). In further embodiments of the disclosure, the polyethylenecomposition has a medium load melt index, 15, of at least about 10.0g/10 min, or at least about 4.0 g/10 min. In still further embodimentsof the disclosure, the polyethylene composition has a medium load meltindex, Is, of from about 5.0 to about 25.0 g/10 min, or from about 5.0to about 20.0 g/10 min, or from about 5.0 to about 17.5 g/10 min, orfrom about 5.0 to about 15.0 g/10 min.

In an embodiment of the disclosure, the polyethylene composition has a“high load” melt index I₂₁ of at least about 100 g/10 min according toASTM D1238 (when conducted at 190° C., using a 21 kg weight). In anotherembodiment of the disclosure, the polyethylene composition has a highload melt index I₂₁, of greater than about 150 g/10 min.

In an embodiment of the disclosure, the polyethylene composition has ahigh load melt index I₂₁, of from 125 to 500 g/10 min, or from 150 to450 g/10 min, or from 150 to 400 g/10 min.

In an embodiment of the disclosure, the polyethylene composition has anumber average molecular weight M_(n), of below about 30,000 g/mol. Inanother embodiment of the disclosure, the polyethylene composition has anumber average molecular weight M_(n), of below about 25,000 g/mol. Inyet another embodiment of the disclosure, the polyethylene compositionhas a number average molecular weight M_(n), of below about 20,000g/mol.

In an embodiment of the present disclosure, the polyethylene compositionhas a molecular weight distribution M_(w)/M_(n), of from 2.0 to 7.0 or anarrower range within this range, including all the numbers encompassedwithin these ranges. For example, in further embodiments of thedisclosure, the polyethylene composition has molecular weightdistribution M_(w)/M_(n), of from 3.0 to 7.0, or from 3.5 to 6.0, orfrom 3.5 to 5.5, or from 2.5 to 6.5, or from 2.5 to 6.0, or from 2.0 to6.0 or from 2.0 to 5.5, or from 2.0 to 5.0, or from 2.0 to 4.5, or from2.5 to 4.25, or from 2.25 to 4.25,

In an embodiment of the disclosure, the polyethylene composition has aZ-average molecular weight, Mz, of below about 300,000 g/mole. Inanother embodiment of the disclosure, the polyethylene composition has aZ-average molecular weight, Mz, of below about 250,000 g/mole. In yetanother embodiment of the disclosure, the polyethylene composition has aZ-average molecular weight, Mz, of below about 200,000 g/mole.

In embodiments of the disclosure, the polyethylene composition has aratio of Z-average molecular weight to weight average molecular weightMz/Mw, of from 2.0 to 4.0, or from 2.0 to 3.75, or from 2.25 to 3.75, orfrom 2.50 to 3.5.

In embodiments of the disclosure, the polyethylene composition has amelt flow ratio defined as I₂₁/I₂, of from about 15 to about 50, or fromabout 20 to 50, or from about 22 to 50, or from about 25 to 45, or fromabout 30 to 45, or from about 30 to 50, or from 22 to 50, or from about22 to less than 50.

In embodiments of the disclosure, the polyethylene composition has amelt flow ratio defined as I₂₁/I₂, of less than 41, or less than 40, orless than 38, or less than 36, or from about 22 to about 40, or fromabout 22 to 38, or from 24 to 38, of from 24 to 40, or from about 24 to36, or from about 26 to about 38, or from about 28 to about 36, or fromabout 28 to about 38, or from about 28 to about 40.

In an embodiment of the disclosure, the polyethylene composition has amelt flow rate defined as I₂₁/I₅, of less than 25. In another embodimentof the disclosure, the polyethylene composition has a melt flow ratedefined as I₂₁/I₅, of less than 20.

In another embodiment of the disclosure, the polyethylene compositionhas a melt flow rate defined as I₂₁/I₅, of less than 15.

In an embodiment of the disclosure, the polyethylene composition has ashear viscosity at about 10⁵ s⁻¹ (240° C.) of less than about 10 (Pa·s).In further embodiments of the disclosure, the polyethylene compositionhas a shear viscosity at about 10⁵ s⁻¹ (240° C.) of less than 7.5 Pa·s,or less than 6.8 Pa·s. Simultaneously, the polyethylene composition mayhave a shear viscosity at about 100 s⁻¹ (240° C.) of less than about 600Pa·s, a shear viscosity at about 200 s⁻¹ (240° C.) of less than about500 Pa·s and a shear viscosity at about 3005-1 (240° C.) of less thanabout 400 Pa·s.

In an embodiment of the disclosure, the polyethylene composition has atleast one type of alpha-olefin that has at least 4 carbon atoms and itscontent is less than about 0.75 mol % as determined by ¹³C NMR. In anembodiment of the disclosure, the polyethylene composition has at leastone type of alpha-olefin that has at least 4 carbon atoms and itscontent is less than about 0.65 mol % as determined by ¹³C NMR. In anembodiment of the disclosure, the polyethylene composition has at leastone type of alpha-olefin that has at least 4 carbon atoms and itscontent is less than about 0.55 mol % as determined by ¹³C NMR. In anembodiment of the disclosure, the polyethylene composition has at leastone type of alpha-olefin that has at least 4 carbon atoms and itscontent is less than about 0.50 mol % as determined by ¹³C NMR. In anembodiment of the disclosure, the polyethylene composition has at leastone type of alpha-olefin that has at least 4 carbon atoms and itscontent is greater than about 0.20 to less than about 0.55 mol % asdetermined by ¹³C NMR.

In an embodiment of the disclosure, the shear viscosity ratio,SVR(_(100,100000)) at 240° C. of the polyethylene composition can befrom about 50 to about 90, or can be from about 55 to about 90, or fromabout 50 to about 85, or from greater than about 50 to about 75. Theshear viscosity ratio SVR(_(100,100000)) is determined by taking theratio of shear viscosity at shear rate of 100 s⁻¹ and shear viscosity atshear rate of 100000 s⁻¹ as measured with a capillary rheometer atconstant temperature (e.g., 240° C.), and two dies with L/D ratio of 20and diameter of 0.06″ (from about 3 to 1000 s⁻¹) and L/D ratio of 20 anddiameter of 0.012″ (from about 1000 to 100000 s⁻¹) respectively.

In an embodiment of the disclosure, the polyethylene composition or amolded article made from the polyethylene composition, has anenvironmental stress crack resistance ESCR Condition B at 100% of atleast about 3 hours, as measured according to ASTM D1693 (at 50° C.using 100% IGEPAL® CO-630, condition B).

In an embodiment of the disclosure, the polyethylene composition or amolded article made from the polyethylene composition, has anenvironmental stress crack resistance ESCR Condition B at 100% of atleast about 3.5 hours, as measured according to ASTM D1693 (at 50° C.using 100% IGEPAL® CO-630, condition B).

In an embodiment of the disclosure, the polyethylene composition or amolded article made from the polyethylene composition, has anenvironmental stress crack resistance ESCR Condition B at 100% of atleast about 4.0 hours, as measured according to ASTM D1693 (at 50° C.using 100% IGEPAL® CO-630, condition B).

In an embodiment of the disclosure, the polyethylene composition or amolded article made from the polyethylene composition, has anenvironmental stress crack resistance ESCR Condition B at 100% of fromabout 3.5 to about 15 hours, as measured according to ASTM D1693 (at 50°C. using 100% IGEPAL® CO-630, condition B).

In embodiments of the disclosure, the polyethylene composition or amolded article (e.g., a plaque) made from the polyethylene composition,has a tensile ultimate elongation of at least 600 percent, or at least700 percent, or at least 800 percent, or at least 850 percent, or atleast 900 percent, or at least 950 percent, or at least 1000 percent. Inan embodiment of the disclosure, the polyethylene composition or amolded article (e.g., a plaque) made from the polyethylene composition,has a tensile ultimate elongation of from 900 to 1400 percent.

In embodiments of the disclosure, the polyethylene composition or amolded article (e.g., a plaque) made from the polyethylene composition,has a tensile ultimate strength of at least 16 MPa, or at least 17 MPa,or at least 18 MPa, or at least 19 MPa, or at least 20 MPa, or at least21 MPa, or at least 22 MPa. In an embodiment of the disclosure, thepolyethylene composition or a molded article (e.g., a plaque) made fromthe polyethylene composition, has a tensile ultimate strength of from 17to 28 MPa.

In embodiments of the disclosure, the polyethylene composition has a“processability indicator” of at least 15, or at least 16, or at least17, or at least 18, or at least 19, or at least 20. In an embodiment ofthe disclosure, the polyethylene composition has a “processabilityindicator” of from 15 to 25.

In an embodiment of the disclosure, the polyethylene composition has amolecular weight distribution M_(w)/M_(n), of from 2.0 to 7.0; a densityof at least 0.950 g/cm³; a melt index I₂ of ≤10 g/10 min; a Z-averagemolecular weight Mz, of less than about 300,000; and a melt flow ratioI₂₁/I₂, less than 41.

In an embodiment of the disclosure, the polyethylene composition or amolded article made from the polyethylene composition, has anenvironmental stress crack resistance ESCR Condition B at 100% of fromabout 3.5 to about 12 hours, as measured according to ASTM D1693 (at 50°C. using 100% IGEPAL® CO-630, condition B).

In an embodiment of the disclosure, the polyethylene composition or amolded article made from the polyethylene composition has a Notched Izodimpact strength of at least about 40 J/m, as measured according to ASTMD256.

In embodiments of the disclosure, the polyethylene composition has aTD/MD shrinkage ratio (for an injection molded disk at about 48 hrs postmolding) of from about 0.90 to about 1.20, or from about 0.90 to about1.15, or from about 0.95 to about 1.15, or from about 0.90 to about1.10, or from about 0.95 to about 1.10, or from about 0.95 to about 1.05when measured according to the Dimensional Stability Test (DST).

In embodiments of the disclosure, the polyethylene composition has a TDshrinkage−MD shrinkage (for an injection molded disk at about 48 hourpost molding time) of from about 0.25 to about 0.25, or from about 0.20to about 0.20, or from about 0.15 to about 0.15, or from about 0.10 toabout 0.10, or from about 0.075 to about 0.075, or from about 0.05 toabout 0.05, when measured according to the Dimensional Stability Test(DST).

In an embodiment of the disclosure, the polyethylene composition of thecurrent disclosure has a density of from 0.950 to 0.960 g/cm³; a meltindex I₂, of from 3 to 12 g/10 min; a molecular weight distributionM_(w)/M_(n), of from 2.0 to 7.0; a number average molecular weightM_(n), of below 30,000; a shear viscosity at 10⁵ s⁻¹ (240° C.) of lessthan 10 (Pa·s), a hexane extractables of less than 0.55%, a notched Izodimpact strength of more than 40 J/m, and an ESCR B at 100% of at leastabout 3.5 hours.

In an embodiment of the disclosure, the polyethylene composition has ahexanes extractables of less than about 0.55%. In further embodiments ofthe disclosure, the polyethylene composition has a hexane extractablesof less than about 0.50%, or less than about 0.45%, or less than about0.40%, or less than about 0.35%.

In an embodiment of the disclosure, the polyethylene composition has astress exponent, defined as Log₁₀[I₆/I₂]/Log₁₀[6.48/2.16], which is≤1.40 or <1.40. In further embodiments of the disclosure, thepolyethylene composition has a stress exponent,Log₁₀[I₆/I₂]/Log₁₀[6.48/2.16] of from 1.22 to 1.40, or from 1.22 to1.38, or from 1.24 to 1.36.

In an embodiment of the disclosure, the polyethylene composition has acomposition distribution breadth index (CDBI(50)), as determined bytemperature elution fractionation (TREF), of about 60 weight percent. Infurther embodiments of the disclosure, the polyethylene composition willhave a CDBI(50) of greater than about 65%, or greater than about 70%, orgreater than about 75%, or greater than about 80%, or greater than about85%.

In an embodiment of the disclosure, the polyethylene composition has acomposition distribution breadth index (CDBI(25)), as determined bytemperature elution fractionation (TREF), of about ≥55 weight percent.In further embodiments of the disclosure, the polyethylene compositionwill have a CDBI(25) of greater than about 60%, or greater than about65%, or from about 55 to about 75%, or from about 60 to about 75%.

The polyethylene composition of this disclosure can be made using anyconventional blending method such as but not limited to physicalblending and in-situ blending by polymerization in multi reactorsystems. For example, it is possible to perform the mixing of the firstethylene copolymer with the second ethylene copolymer by molten mixingof the two preformed polymers. One embodiment uses processes in whichthe first and second ethylene copolymers are prepared in at least twosequential polymerization stages, however, both in-series or anin-parallel dual reactor process are contemplated for use in the currentdisclosure. Gas phase, slurry phase or solution phase reactor systemsmay be used. In one embodiment a solution phase reactor systems is used.

In some embodiments mixed catalyst single reactor systems may also beemployed to make the polymer compositions disclosed herein.

In an embodiment of the current disclosure, a dual reactor solutionpolymerization process is used as has been described in for example U.S.Pat. No. 6,372,864 and U.S. Application Publication No. 20060247373A1.

In some embodiments the catalysts used in the current disclosure will beso called single site catalysts based on a group 4 metal having at leastone cyclopentadienyl ligand. Examples of such catalysts includemetallocenes, constrained geometry catalysts, and phosphiniminecatalysts used, for example, in combination with activators selectedfrom methylaluminoxanes, boranes, or ionic borate salts and are furtherdescribed in U.S. Pat. Nos. 3,645,992; 5,324,800; 5,064,802; 5,055,438;6,689,847; 6,114,481, and 6,063,879. Such single site catalysts aredistinguished from traditional Ziegler-Natta or Phillips catalysts whichare also well known in the art. In some embodiments single sitecatalysts produce ethylene copolymers having a molecular weightdistribution (M_(w)/M_(n)) of less than about 3.0 and a compositiondistribution breadth index CDBI(50) of greater than about 65%.

In an embodiment of the disclosure, a single site catalyst is used tomake an ethylene copolymer having a CDBI(50) of at least about 65% byweight, or at least about 70%, or at least about 75%, or at least about80%, or at least about 85%, during solution phase polymerization in asingle reactor, for the preparation of each of the first and the secondethylene copolymers.

In an embodiment of the disclosure, homogeneously branched ethylenecopolymers are prepared using an organometallic complex of a group 3, 4or 5 metal that is further characterized as having a phosphinimineligand. Such a complex, when active toward olefin polymerization, isknown generally as a phosphinimine (polymerization) catalyst. Somenon-limiting examples of phosphinimine catalysts can be found in U.S.Pat. Nos. 6,342,463; 6,235,672; 6,372,864; 6,984,695; 6,063,879;6,777,509, and 6,277,931.

Some non-limiting examples of metallocene catalysts can be found in U.S.Pat. Nos. 4,808,561; 4,701,432; 4,937,301; 5,324,800; 5,633,394;4,935,397; 6,002,033, and 6,489,413. Some non-limiting examples ofconstrained geometry catalysts can be found in U.S. Pat. Nos. 5,057,475;5,096,867; 5,064,802; 5,132,380; 5,703,187, and 6,034,021.

In an embodiment of the disclosure, use of a single site catalyst thatdoes not produce long chain branching (LCB) is used. Hexyl (C6) branchesdetected by NMR are excluded from the definition of a long chain branchas disclosed herein.

Without wishing to be bound by any single theory, long chain branchingcan increase viscosity at low shear rates, thereby negatively impactingcycle times during the manufacture of bottle closure assemblies, such asduring the processes of injection molding or compression molding. Longchain branching may be determined using ¹³C NMR methods and may bequantitatively assessed using the method disclosed by Randall in Rev.Macromol. Chem. Phys. C29 (2 and 3), p. 285.

In an embodiment of the disclosure, the polyethylene composition willcontain fewer than 0.3 long chain branches per 1000 carbon atoms. Inanother embodiment of the disclosure, the polyethylene composition willcontain fewer than 0.01 long chain branches per 1000 carbon atoms.

In an embodiment of the disclosure, the polyethylene composition isprepared by contacting ethylene and at least one alpha-olefin with apolymerization catalyst under solution phase polymerization conditionsin at least two polymerization reactors (for an example of solutionphase polymerization conditions see for example U.S. Pat. Nos. 6,372,864and 6,984,695 and U.S. Patent Application 20060247373A1).

In an embodiment of the disclosure, the polyethylene composition isprepared by contacting at least one single site polymerization catalystsystem (including at least one single site catalyst and at least oneactivator) with ethylene and a least one comonomer (e.g., a C3-C8alpha-olefin) under solution polymerization conditions in at least twopolymerization reactors.

In an embodiment of the disclosure, a group 4 single site catalystsystem, including a single site catalyst and an activator, is used in asolution phase dual reactor system to prepare a polyethylene compositionby polymerization of ethylene in the presence of an alpha-olefincomonomer.

In an embodiment of the disclosure, a group 4 single site catalystsystem, including a single site catalyst and an activator, is used in asolution phase dual reactor system to prepare a polyethylene compositionby polymerization of ethylene in the presence of 1-octene.

In an embodiment of the disclosure, a group 4 phosphinimine catalystsystem, including a phosphinimine catalyst and an activator, is used ina solution phase dual reactor system to prepare a polyethylenecomposition by polymerization of ethylene in the presence of analpha-olefin comonomer.

In an embodiment of the disclosure, a group 4 phosphinimine catalystsystem, including a phosphinimine catalyst and an activator, is used ina solution phase dual reactor system to prepare a polyethylenecomposition by polymerization of ethylene in the presence of 1-octene.

In an embodiment of the disclosure, a solution phase dual reactor systemincludes two solution phase reactors connected in series.

In an embodiment of the disclosure, a polymerization process to preparethe polyethylene composition includes contacting at least one singlesite polymerization catalyst system (including at least one single sitecatalyst and at least one activator) with ethylene and at least onealpha-olefin comonomer under solution polymerization conditions in atleast two polymerization reactors.

In an embodiment of the disclosure, a polymerization process to preparethe polyethylene composition includes contacting at least one singlesite polymerization catalyst system with ethylene and at least onealpha-olefin comonomer under solution polymerization conditions in afirst reactor and a second reactor configured in series.

In an embodiment of the disclosure, a polymerization process to preparethe polyethylene composition includes contacting at least one singlesite polymerization catalyst system with ethylene and at least onealpha-olefin comonomer under solution polymerization conditions in afirst reactor and a second reactor configured in series, with the atleast one alpha-olefin comonomer being fed exclusively to the firstreactor.

In one embodiment, the production of the polyethylene composition asdisclosed herein may include an extrusion or compounding step. Suchsteps are well known in the art.

In one embodiment, the polyethylene composition can comprise furtherpolymer components in addition to the first and second ethylenepolymers. Such polymer components include polymers made in situ orpolymers added to the polymer composition during an extrusion orcompounding step.

Optionally, additives can be added to the polyethylene composition.Additives can be added to the polyethylene composition during anextrusion or compounding step, but other suitable known methods will beapparent to a person skilled in the art. The additives can be added asis or as part of a separate polymer component (i.e. not the first orsecond ethylene polymers described above) added during an extrusion orcompounding step. Suitable additives are known in the art and includebut are not-limited to antioxidants, phosphites and phosphonites,nitrones, antacids, UV light stabilizers, UV absorbers, metaldeactivators, dyes, fillers and reinforcing agents, nano-scale organicor inorganic materials, antistatic agents, lubricating agents such ascalcium stearates, slip additives such as erucimide or behenamide, andnucleating agents (including nucleators, pigments or any other chemicalswhich may provide a nucleating effect to the polyethylene composition).The additives that can be optionally added may be added in amount of upto about 20 weight percent (wt. %).

In an embodiment of the disclosure, one or more nucleating agent(s) maybe introduced into the polyethylene composition by kneading a mixture ofthe polymer, usually in powder or pellet form, with the nucleatingagent, which may be utilized alone or in the form of a concentratecontaining further additives such as stabilizers, pigments, antistatics,UV stabilizers and fillers. In an embodiment, a nucleating agent is amaterial which is wetted or absorbed by the polymer, is insoluble in thepolymer, has a melting point higher than that of the polymer, and it ishomogeneously dispersible in the polymer melt in as fine a form aspossible (about 1 to about 10 μm). Compounds known to have a nucleatingcapacity for polyolefins include salts of aliphatic monobasic or dibasicacids or arylalkyl acids, such as sodium succinate or aluminumphenylacetate; and alkali metal or aluminum salts of aromatic oralicyclic carboxylic acids such as sodium β-naphthoate. Another compoundknown to have nucleating capacity is sodium benzoate. Another compoundknown to have nucleating capacity is talc. The effectiveness ofnucleation may be monitored microscopically by observation of the degreeof reduction in size of the spherulites into which the crystallites areaggregated.

Examples of nucleating agents which are commercially available and whichmay be added to the polyethylene composition are dibenzylidene sorbitalesters (such as the products sold under the trademark Millad™ 3988 byMilliken Chemical and Irgaclear by Ciba Specialty Chemicals). Furtherexamples of nucleating agents which may added to the polyethylenecomposition include the cyclic organic structures disclosed in U.S. Pat.No. 5,981,636 (and salts thereof, such as disodium bicyclo[2.2.1]heptene dicarboxylate); the saturated versions of the structuresdisclosed in U.S. Pat. No. 5,981,636 (as disclosed in U.S. Pat. No.6,465,551; Zhao et al., to Milliken); the salts of certain cyclicdicarboxylic acids having a hexahydrophtalic acid structure (or “HHPA”structure) as disclosed in U.S. Pat. No. 6,599,971 (Dotson et al., toMilliken); and phosphate esters, such as those disclosed in U.S. Pat.No. 5,342,868 and those sold under the trade names NA-11 and NA-21 byAsahi Denka Kogyo, cyclic dicarboxylates and the salts thereof, such asthe divalent metal or metalloid salts, (particularly, calcium salts) ofthe HHPA structures disclosed in U.S. Pat. No. 6,599,971. For clarity,the HHPA structure includes a ring structure with six carbon atoms inthe ring and two carboxylic acid groups which are substituents onadjacent atoms of the ring structure. The other four carbon atoms in thering may be substituted, as disclosed in U.S. Pat. No. 6,599,971. Anexample is 1,2-cyclohexanedicarboxylic acid, calcium salt (CAS registrynumber 491589-22-1). Still further examples of nucleating agents whichmay added to the polyethylene composition include those disclosed inWO2015042561, WO2015042563, WO2015042562, and WO 2011050042.

Many of the above described nucleating agents may be difficult to mixwith the polyethylene composition that is being nucleated and it isknown to use dispersion aids, such as for example, zinc stearate, tomitigate this problem.

In an embodiment of the disclosure, the nucleating agents are welldispersed in the polyethylene composition.

In an embodiment of the disclosure, the amount of nucleating agent usedis comparatively small (from 100 to 3000 parts by million per weight(based on the weight of the polyethylene composition)) so it will beappreciated by those skilled in the art that some care must be taken toensure that the nucleating agent is well dispersed. In an embodiment ofthe disclosure, the nucleating agent is added in finely divided form(less than 50 microns, especially less than 10 microns) to thepolyethylene composition to facilitate mixing. This type of “physicalblend” (i.e., a mixture of the nucleating agent and the resin in solidform) is, in some embodiments, preferable to the use of a “masterbatch”of the nucleator (where the term “masterbatch” refers to the practice offirst melt mixing the additive—the nucleator, in this case—with a smallamount of the polyethylene composition resin—then melt mixing the“masterbatch” with the remaining bulk of the polyethylene compositionresin).

In an embodiment of the disclosure, an additive such as nucleating agentmay be added to the polyethylene composition by way of a “masterbatch”,where the term “masterbatch” refers to the practice of first melt mixingthe additive (e.g., a nucleator) with a small amount of the polyethylenecomposition, followed by melt mixing the “masterbatch” with theremaining bulk of the polyethylene composition.

In an embodiment of the disclosure, the polyethylene composition furtherincludes a nucleating agent or a mixture of nucleating agents.

In an embodiment of the disclosure, homogeneously branched polyethylenecopolymers are prepared using an organometallic complex of a group 3, 4or 5 metal that is further characterized as having a phosphinimineligand. Such a complex, when active toward olefin polymerization, isknown generally as a phosphinimine (polymerization) catalyst.

In an embodiment of the disclosure, the polyethylene compositionsdescribed above are used in the formation of molded articles. Forexample, articles formed by compression molding and injection moldingare contemplated.

The polyethylene compositions described above are used in the formationof bottle closure assemblies. For example, bottle closure assembliesformed in part on in whole by compression molding or injection moldingare contemplated.

In one embodiment, the bottle closure assembly includes the polyethylenecomposition described above which have very good dimensional stability,good organoleptic properties, good toughness, and reasonable ESCRvalues. The bottle closure assemblies are well suited for sealingbottles, containers, and the like, for examples bottles that may containdrinkable water, and other foodstuffs, including but not limited toliquids that are pressurized (e.g., carbonated beverages orappropriately pressurized drinkable liquids). The bottle closureassemblies may also be used for sealing bottles containing drinkablewater or non-carbonated beverages (e.g., juice). Other applications,include bottle closure assemblies for bottles and containers containingfoodstuffs, such as for example ketchup bottles and the like.

The bottle closure assemblies of the current disclosure can be madeaccording to any known method, including for example injection moldingor compression molding techniques that are well known to persons skilledin the art. Hence, in an embodiment of the disclosure, a bottle closureassembly including the polyethylene composition (defined above) isprepared with a process including at least one compression molding stepand/or at least one injection molding step.

The disclosure is further illustrated by the following non-limitingexamples.

Examples

Melt indexes, I₂, I₅, I₆, and I₂₁ for the polyethylene composition weremeasured according to ASTM D1238 (when conducted at 190° C., using a2.16 kg, a 5 kg, a 6.48 kg and a 21 kg weight respectively).

M_(n), M_(w), and M_(z) (g/mol) were determined by high temperature GelPermeation Chromatography with differential refractive index detectionusing universal calibration (e.g., ASTM-D6474-99). GPC data was obtainedusing an instrument sold under the trade name “Waters 150c”, with1,2,4-trichlorobenzene as the mobile phase at 140° C. The samples wereprepared by dissolving the polymer in this solvent and were run withoutfiltration. Molecular weights are expressed as polyethylene equivalentswith a relative standard deviation of 2.9% for the number averagemolecular weight (“M_(n)”) and 5.0% for the weight average molecularweight (“M_(w)”). The molecular weight distribution (MWD) is the weightaverage molecular weight divided by the number average molecular weight,M_(w)/M_(n). The z-average molecular weight distribution is M_(z)/M_(n).Polymer sample solutions (1 to 2 mg/mL) were prepared by heating thepolymer in 1,2,4-trichlorobenzene (TCB) and rotating on a wheel for 4hours at 150° C. in an oven. The antioxidant2,6-di-tert-butyl-4-methylphenol (BHT) was added to the mixture in orderto stabilize the polymer against oxidative degradation. The BHTconcentration was 250 ppm. Sample solutions were chromatographed at 140°C. on a PL 220 high-temperature chromatography unit equipped with fourShodex columns (HT803, HT804, HT805 and HT806) using TCB as the mobilephase with a flow rate of 1.0 mL/minute, with a differential refractiveindex (DRI) as the concentration detector. BHT was added to the mobilephase at a concentration of 250 ppm to protect the columns fromoxidative degradation. The sample injection volume was 200 mL. The rawdata were processed with Cirrus GPC software. The columns werecalibrated with narrow distribution polystyrene standards. Thepolystyrene molecular weights were converted to polyethylene molecularweights using the Mark-Houwink equation, as described in the ASTMstandard test method D6474.

Primary melting peak (° C.), heat of fusion (J/g), and crystallinity (%)was determined using differential scanning calorimetry (DSC) as follows:the instrument was first calibrated with indium; after the calibration,a polymer specimen is equilibrated at 0° C. and then the temperature wasincreased to 200° C. at a heating rate of 10° C./min; the melt was thenkept isothermally at 200° C. for five minutes; the melt was then cooledto 0° C. at a cooling rate of 10° C./min and kept at 0° C. for fiveminutes; the specimen was then heated to 200° C. at a heating rate of10° C./min. The DSC Tm, heat of fusion, and crystallinity are reportedfrom the 2^(nd) heating cycle.

The short chain branch frequency (SCB per 1000 carbon atoms) of thepolyethylene composition was determined by Fourier Transform InfraredSpectroscopy (FTIR) as per the ASTM-D6645-01 method. A Thermo-Nicolet750 Magna-IR Spectrophotometer equipped with OMNIC version 7.2a softwarewas used for the measurements. Unsaturations in the polyethylenecomposition were also determined by Fourier Transform InfraredSpectroscopy (FTIR) as per ASTM-D3124-98. Comonomer content can also bemeasured using ¹³C NMR techniques as discussed in Randall, Rev.Macromol. Chem. Phys., C29 (2&3), p 285; U.S. Pat. No. 5,292,845, and WO2005/121239.

Polyethylene composition density (g/cm³) was measured according to ASTMD792.

Hexane extractables were determined according to ASTM D5227.

Shear viscosity was measured by using a Kayeness WinKARS CapillaryRheometer (model #D5052M-115). For the shear viscosity at lower shearrates, a die having a die diameter of 0.06 inch and L/D ratio of 20 andan entrance angle of 180 degrees was used. For the shear viscosity athigher shear rates, a die having a die diameter of 0.012 inch and L/Dratio of 20 was used.

The “processability indicator” as used herein is defined as:Processability Indicator=100/η(10⁵ s⁻¹, 240° C.); where η is the shearviscosity measured at 10⁵ s⁻¹ at 240° C.

To determine CDBI(50), a solubility distribution curve is firstgenerated for the polyethylene composition. This is accomplished usingdata acquired from the TREF technique. This solubility distributioncurve is a plot of the weight fraction of the copolymer that issolubilized as a function of temperature. This is converted to acumulative distribution curve of weight fraction versus comonomercontent, from which the CDBI(50) is determined by establishing theweight percentage of a copolymer sample that has a comonomer contentwithin 50% of the median comonomer content on each side of the median(see WO 93/03093 and U.S. Pat. No. 5,376,439). The CDBI(25) isdetermined by establishing the weight percentage of a copolymer samplethat has a comonomer content within 25% of the median comonomer contenton each side of the median

The temperature rising elution fractionation (TREF) method used hereinwas as follows. Polymer samples (50 to 150 mg) were introduced into thereactor vessel of a crystallization-TREF unit (Polymer Char™). Thereactor vessel was filled with to 40 ml 1,2,4-trichlorobenzene (TCB),and heated to the desired dissolution temperature (e.g., 150° C.) for 1to 3 hours. The solution (0.5 to 1.5 ml) was then loaded into the TREFcolumn filled with stainless steel beads. After equilibration at a givenstabilization temperature (e.g., 110° C.) for 30 to 45 minutes, thepolymer solution was allowed to crystallize with a temperature drop fromthe stabilization temperature to 30° C. (0.1 or 0.2° C./minute). Afterequilibrating at 30° C. for 30 minutes, the crystallized sample waseluted with TCB (0.5 or 0.75 mL/minute) with a temperature ramp from 30°C. to the stabilization temperature (0.25 or 1.0° C./minute). The TREFcolumn was cleaned at the end of the run for 30 minutes at thedissolution temperature. The data were processed using Polymer Charsoftware, Excel spreadsheet and TREF software developed in-house.

High temperature GPC equipped with an online FTIR detector (GPC-FTIR)was used to measure the comonomer content as the function of molecularweight.

Plaques molded from the polyethylene compositions were tested accordingto the following ASTM methods: Bent Strip Environmental Stress CrackResistance (ESCR) at Condition B at 100% IGEPAL® CO-630 at 50° C., ASTMD1693; notched Izod impact properties, ASTM D256; Flexural Properties,ASTM D 790; Tensile properties, ASTM-D 638; Vicat softening point,ASTM-D 1525; Heat deflection temperature, ASTM-D 648.

Dynamic mechanical analyses were carried out with a rheometer, namelyRheometrics Dynamic Spectrometer (RDS-II) or Rheometrics SR5 or ATSStresstech, on compression molded samples under nitrogen atmosphere at190° C., using 25 mm diameter cone and plate geometry. The oscillatoryshear experiments were done within the linear viscoelastic range ofstrain (10% strain) at frequencies from 0.05 to 100 rad/s. The values ofstorage modulus (G′), loss modulus (G″), complex modulus (G*) andcomplex viscosity (1*) were obtained as a function of frequency. Thesame rheological data can also be obtained by using a 25 mm diameterparallel plate geometry at 190° C. under nitrogen atmosphere.

The dimensional stability of the polyethylene compositions wasdetermined as follows: A 150-ton×12-Oz Cincinnati Milacron injectionmolding machine (Hydradamp 150T 12 oz PC-111, serial #4001 A21/79-38)with a 2 inch (50.8 mm) screw was used to produce parts according to theconditions listed in Table 1. The mold was an ASTM test mold, whichmakes tensile test specimens with an overall length of 1.30 inches, anoverall width of 0.75 inch, and a thickness of 0.12 inch; tensile testspecimens with an overall length of 1.375 inch, an overall width of0.375 inch, and a thickness of 0.12 inch; tensile test specimens with anoverall length of 2.5 inch, an overall width of 0.375 inch, and athickness of 0.12 inch; flexural modulus bars with a length of 5 inch, awidth of 0.50 inch, and a thickness of either 0.12 inch or 0.75 inch,and an impact round disk with a diameter of 2 inch and a thickness of0.12 inch. Immediately after molding, the injection-molded disk wasremoved from the runner (note: an injection molded disk with a 2 inchdiameter and a thickness of 0.12 inches was used for measurementsdisclosed herein). The diameters in both the machine (or in-flow)direction (MD) and transverse-flow direction (TD) are then measured atroom temperature (23±2° C.) after 1, 24, and 48 hours of molding.Shrinkage at time t is defined as the percentage change in dimension atmeasurement time from the original mold dimensions:

Shrinkage percent=(Mold dimension−Specimen dimension at time t)×100/Molddimension

Thus, MD shrinkage is the shrinkage measured on the disk in the flowdirection, and Transverse direction (TD) shrinkage is the shrinkagemeasured in the cross-flow direction. Here, the isotropic shrinkage isdefined as the equal shrinkage in both the flow direction (in-flow) andthe transverse direction. Differential shrinkage is defined as TDshrinkage minus MD shrinkage (an indication of part planarity orflatness or the extent of part warpage). The smaller the difference itis, the better the part planarity. A TD/MD shrinkage ratio, the TDshrinkage divided by MD shrinkage, can also be used as a measure of theextent of isotropic shrinkage (the closer to unity it is, the better thepart planarity). The molding parameters used are summarized in Table 1.

TABLE 1 Barrel Temperature (° C.), feed Section 215.5 Barrel Temperature(° C.), Trans. Section 237.8 Barrel Temperature (° C.), Metering Section237.8 Barrel Temperature (° C.), Nozzle 237.8 Injection Time-High (s) 6Injection Time-Low (s) 23 Cooling Time (s) 30 Decompression Time (s)0.07 Clamp Open Time (s) 0.02 Mold Close Time (s) 60 Cycle Time (s) 62Screw Speed (rpm) 20 Injection rate Max Shot size (inch) 1.5 Cushion(inch) 0.2 Injection Pressure-High (psi) 5250 Injection Pressure-Low(psi) 5000 Back Pressure (psi) 1000 Clamp Pressure-High (psi) 1850 ClampPressure-Low (psi) 1000 Mold Temperature (° C.), represented 11.7 bycooling water Cycle Auto

Examples of the polyethylene compositions were produced in a dualreactor solution polymerization process in which the contents of thefirst reactor flow into the second reactor. This in-series “dualreactor” process produces an “in-situ” polyethylene blend (i.e., thepolyethylene composition). Note, that when an in-series reactorconfiguration is used, un-reacted ethylene monomer, and un-reactedalpha-olefin comonomer present in the first reactor will flow into thedownstream second reactor for further polymerization.

For the polyethylene compositions of Examples 1-6, although noco-monomer is fed directly to the downstream second reactor, an ethylenecopolymer is nevertheless formed in second reactor due to thesignificant presence of un-reacted 1-octene flowing from the firstreactor to the second reactor where it is copolymerized with ethylene.Each reactor is sufficiently agitated to give conditions in whichcomponents are well mixed. The volume of the first reactor was 12 litersand the volume of the second reactor was 22 liters. These are the pilotplant scales. The first reactor was operated at a pressure of 10500 to35000 kPa and the second reactor was operated at a lower pressure tofacilitate continuous flow from the first reactor to the second. Thesolvent employed was methylpentane. The process operates usingcontinuous feed streams. The catalyst employed in the dual reactorsolution process experiments was a phosphinimine catalyst, which was atitanium complex having a phosphinimine ligand (e.g., (tert-butyl)₃P═N),a cyclopentadienide ligand (e.g., Cp) and two activatable ligands, suchas but not limited to chloride ligands (note: “activatable ligands” areremoved, by for example electrophilic abstraction using a co-catalyst oractivator to generate an active metal center). A boron based co-catalyst(e.g., Ph₃CB(C₆F₅)₄) was used in approximately stoichiometric amountsrelative to the titanium complex. Commercially availablemethylaluminoxane (MAO) was included as a scavenger at an Al:Ti of about40:1. In addition, 2,6-di-tert-butylhydroxy-4-ethylbenzene was added toscavenge free trimethylaluminum within the MAO in a ratio of Al:OH ofabout 0.5:1.

Polyethylene resins Examples A, B, and C are made using a single sitephosphinimine catalyst in a dual reactor solution process in which allthe comonomer is fed to the second reactor.

Polyethylene resin Example D is an injection molding grade believed tobe an ethylene homopolymer made with a traditional polymerizationcatalyst (e.g., a Ziegler-Natta polymerization catalyst) and which iscommercially available from INEOS as J60-800-178.

Polyethylene resin Example E is an injection molding grade polyethylenehomopolymer, commercially available resin from NOVA Chemicals® asIG-454-A.

The polyethylene compositions of Examples 1-6 are made using a singlesite phosphinimine catalyst in a dual reactor solution process asdescribed above and have an ESCR at condition B100 of greater than 3.5hours and a SCB1/SCB2 ratio of greater than 1.0. Examples 1-6 also havea Mz value of less than 300,000.

The polymerization conditions used to make the polyethylene compositionsare provided in Table 2.

Polyethylene composition properties are described in Tables 3.

Calculated properties for the first ethylene copolymer and the secondethylene copolymer for selected polyethylene compositions are providedin Table 4 (see “Copolymerization Reactor Modeling” below for methods).

The properties of pressed plaques made from polyethylene compositionsare provided in Table 5.

Information on dimensional stability for polyethylene compositionsresins is provided in Table 6.

Copolymerization Reactor Modeling

For multicomponent (or bimodal resins) polyethylene polymers with verylow comonomer content, it can be difficult to reliably estimate theshort chain branching (and subsequently polyethylene resin density bycombining other information) of each polymer component by mathematicaldeconvolution of GPC-FTIR data, as was done in, for example, U.S. Pat.No. 8,022,143. Instead, the M_(w), M_(n), M_(z), M_(w)/M_(n), and theshort chain branching per thousand carbons (SCB/1000 C) of the first andsecond copolymers were calculated herein, by using a reactor modelsimulation using the input conditions which were employed for actualpilot scale run conditions (for references on relevant reactor modelingmethods, see “Copolymerization” by A. Hamielec, J. MacGregor, and A.Penlidis in Comprehensive Polymer Science and Supplements, volume 3,Chapter 2, page 17, Elsevier, 1996 and “Copolymerization of Olefins in aSeries of Continuous Stirred-Tank Slurry-Reactors using HeterogeneousZiegler-Natta and Metallocene Catalysts. I. General Dynamic MathematicalModel” by J. B. P Soares and A. E Hamielec in Polymer ReactionEngineering, 4(2&3), p 153, 1996.) This type of model is consideredreliable for the estimate of comonomer (e.g., 1-octene) content even atlow comonomer incorporation levels, since the ethylene conversion,ethylene input flow and comonomer input flow can be obtained directlyfrom the experimental conditions and because the reactive ratio (seebelow) can be reliably estimated for the catalyst systems disclosedherein. For clarity, the “monomer” or “monomer 1” represent ethylene,while the terms “comonomer” or “monomer 2”, represent 1-octene.

The model takes for input the flow of several reactive species (e.g.,catalyst, monomer such as ethylene, comonomer such as 1-octene,hydrogen, and solvent) going to each reactor, the temperature (in eachreactor), and the conversion of monomer (in each reactor), andcalculates the polymer properties (of the polymer made in each reactor,i.e., the first and second ethylene copolymers) using a terminal kineticmodel for continuously stirred tank reactors (CSTRs) connected inseries. The “terminal kinetic model” assumes that the kinetics dependupon the monomer unit within the polymer chain on which the activecatalyst site is located (see “Copolymerization” by A. Hamielec, J.MacGregor, and A. Penlidis in Comprehensive Polymer Science andSupplements, Volume 3, Chapter 2, page 17, Elsevier, 1996). In themodel, the copolymer chains are assumed to be of reasonably largemolecular weight to ensure that the statistics of monomer/comonomer unitinsertion at the active catalyst center is valid and thatmonomers/comonomers consumed in routes other than propagation arenegligible. This is known as the “long chain” approximation.

The terminal kinetic model for polymerization includes reaction rateequations for activation, initiation, propagation, chain transfer, anddeactivation pathways. This model solves the steady-state conservationequations (e.g., the total mass balance and heat balance) for thereactive fluid which includes the reactive species identified above.

The total mass balance for a generic CSTR with a given number of inletsand outlets is given by:

0=Σ_(i) {dot over (m)} _(i)  (1)

where {dot over (m)}_(i) represents the mass flow rate of individualstreams with index i indicating the inlet and outlet streams.

Equation (1) can be further expanded to show the individual species andreactions:

$\begin{matrix}{0 = {\frac{{\sum}_{i}m{\overset{.}{x}}_{{\iota}_{J}}/M_{i}}{\rho_{mix}V} + {R_{j}/\rho_{mix}}}} & (2)\end{matrix}$

where M_(i) is the average molar weight of the fluid inlet or outlet(i), x_(ij) is the mass fraction of species j in stream i, ρ_(mix) isthe molar density of the reactor mixture, V is the reactor volume, R_(j)is the reaction rate for species j, which has units of kmol/m³s.

The total heat balance is solved for an adiabatic reactor and is givenby:

0=(Σ{dot over (m)} _(i) ΔH _(i) +q _(Rx) V+{dot over (W)}−{dot over(Q)})  (3)

where, {dot over (m)}_(i) is the mass flow rate of stream i (inlet oroutlet), ΔH_(i) is the difference in enthalpy of stream i versus areference state, q_(Rx) is the heat released by reaction(s), V is thereactor volume, {dot over (W)} is the work input (i.e., agitator), {dotover (Q)} is the heat input/loss.

The catalyst concentration input to each reactor is adjusted to matchthe experimentally determined ethylene conversion and reactortemperature values in order solve the equations of the kinetic model(e.g., propagation rates, heat balance, and mass balance).

The H₂ concentration input to each reactor may be likewise adjusted sothat the calculated molecular weight distribution of a polymer made overboth reactors (and, hence, the molecular weight of polymer made in eachreactor) matches that which is observed experimentally.

The degree of polymerization (DPN) for a polymerization reaction isgiven by the ratio of the rate of chain propagation reactions over therate of chain transfer/termination reactions:

$\begin{matrix}{{D{PN}} = \frac{{k_{p11}{\phi_{1}\left\lbrack m_{1} \right\rbrack}} + {k_{p12}{\phi_{1}\left\lbrack m_{2} \right\rbrack}} + {k_{p21}{\phi_{2}\left\lbrack m_{2} \right\rbrack}}}{{{k_{{tm}11}\left\lbrack m_{1} \right\rbrack}\phi_{1}} + {{k_{{tm}12}\left\lbrack m_{2} \right\rbrack}\phi_{1}} + {{k_{{tm}21}\left\lbrack m_{2} \right\rbrack}\phi_{2}} + {k_{{ts}1}\phi_{1}} + {k_{{ts}2}\phi_{2}} + {k_{tH1}\lbrack H\rbrack} + {k_{tH2}\lbrack H\rbrack}}} & (4)\end{matrix}$

where k_(p12) is the propagation rate constant for adding monomer 2 to agrowing polymer chain ending with monomer 1, [m₁] is the molarconcentration of monomer 1 (ethylene) in the reactor, [m₂] is the molarconcentration of monomer 2 (1-octene) in the reactor, k_(tm12) thetermination rate constant for chain transfer to monomer 2 for a growingchain ending with monomer 1, k_(ts1) is rate constant for thespontaneous chain termination for a chain ending with monomer 1, k_(tH1)is the rate constant for the chain termination by hydrogen for a chainending with monomer 1. ϕ₁ and ϕ₂ and the fraction of catalyst sitesoccupied by a chain ending with monomer 1 or monomer 2 respectively.

The number average molecular weight (Mn) for a polymer follows from thedegree of polymerization and the molecular weight of a monomer unit.From the number average molecular weight of polymer in each reactor, andassuming a Flory distribution for a single site catalyst, the molecularweight distribution is determined for the polymer formed in eachreactor:

w(n)=τ² ne ^(−τn)  (5)

where

${\tau = \frac{1}{DPN}},$

and w(n) is the weight fraction of polymer having a chain length n.

The Flory distribution can be transformed into the common log scaled GPCtrace by applying:

$\begin{matrix}{\frac{dW}{d\log(M)} = {\ln(10)\frac{n^{2}}{DPN^{2}}e^{({- \frac{n}{DPN}})}}} & (6)\end{matrix}$

where

$\frac{dW}{d\log\left( {MW} \right)}$

is the differential weight fraction of polymer with a chain length n(n=MW/28 where 28 is the molecular weight of the polymer segmentcorresponding to a C₂H₄ unit) and DPN is the degree of polymerization ascalculated by Equation (4). From the Flory model, the M_(w) and theM_(z) of the polymer made in each reactor are: M_(w)=2×M_(n) andM_(z)=1.5×M_(w).

The overall molecular weight distribution over both reactors is simplythe sum of the molecular weight distribution of polymer made in eachreactor, and where each Flory distribution is multiplied by the weightfraction of polymer made in each reactor:

$\begin{matrix}{\frac{d\overset{\_}{W}}{d\log\left( {MW} \right)} = {{w_{R1}\left( {\ln(10)\frac{n^{2}}{{DP}N_{R1}^{2}}e^{({- \frac{n}{DPN_{R1}}})}} \right)} + {w_{R2}\left( {\ln(10)\frac{n^{2}}{{DPN}_{R2}^{2}}e^{({- \frac{n}{DPN_{R2}}})}} \right)}}} & (7)\end{matrix}$

where dW/d log(MW) is the overall molecular weight distributionfunction, w_(R1) and w_(R2) are the weight fraction of polymer made ineach reactor, DPN₁ and DPN₂ is the average chain length of the polymermade in each reactor (i.e. DPN₁=M_(nR1)/28). The weight fraction ofmaterial made in each reactor is determined from knowing the mass flowof monomer and comonomer into each reactor along with knowing theconversions for monomer and comonomer in each reactor.

The moments of the overall molecular weight distribution (or themolecular weight distribution of polymer made in each reactor) can becalculated using equations 8a, 8b and 8c (a Flory Model is assumedabove, but the below generic formula apply to other model distributionsas well):

$\begin{matrix}{\overset{\_}{M_{n}} = \frac{\sum_{i}w_{i}}{{\sum}_{i}\frac{w_{i}}{M_{i}}}} & \left( {8a} \right)\end{matrix}$ $\begin{matrix}{\overset{\_}{M_{w}} = \frac{\sum_{i}{w_{i}M_{i}}}{\sum_{i}w_{i}}} & \left( {8b} \right)\end{matrix}$ $\begin{matrix}{\overset{\_}{M_{z}} = \frac{\sum_{i}{w_{i}M_{i}^{2}}}{{\sum}_{i}w_{i}M_{i}}} & \left( {8c} \right)\end{matrix}$

The comonomer content in the polymer product (in each reactor) may alsobe calculated using the terminal kinetic model and long chainapproximations discussed above (see A. Hamielec, J. MacGregor, and A.Penlidis. Comprehensive Polymer Science and Supplements, volume 3,chapter Copolymerization, page 17, Elsevier, 1996).

For a given catalyst system, the comonomer (e.g., 1-octene)incorporation is a function of the monomer (e.g., ethylene) conversion,the comonomer to monomer ratio in the reactor (γ) and the reactivityratio of monomer 1 (e.g., ethylene) over monomer 2 (e.g., 1-octene):

r ₁ =k _(p11) /k _(p12).

For a CSTR, the molar ratio of ethylene to comonomer in the polymer (Y)can be estimated knowing the reactivity ratio r₁ of the catalyst systemand knowing the ethylene conversion in the reactor (Q_(m1)). A quadraticequation can be derived using the May and Lewis equation forinstantaneous comonomer incorporation (see “Copolymerization” by A.Hamielec, J. MacGregor, and A. Penlidis in Comprehensive Polymer Scienceand Supplements, Volume 3, Chapter 2, page 17, Elsevier, 1996) andsolving the mass balance around the reaction. The molar ratio ofethylene to 1-octene in the polymer is the negative root of thefollowing quadratic equation:

$\begin{matrix}{{{{- Y^{2}}\frac{\gamma}{4}} + {\left\lbrack {r_{1} + {Q_{m1}\left( {1 - r_{1}} \right)} + \frac{\gamma}{4}} \right\rbrack Y} - Q_{m1}} = 0} & (9)\end{matrix}$

where Y is the molar ratio of ethylene to 1-octene in the polymer, γ isthe mass flow ratio of 1-octene to ethylene going the reactor, r₁ is thereactivity ratio of monomer 1 to monomer 2 for the catalyst system(r₁=k_(p11)/k_(p12)) and Q_(m1) is the ethylene monomer fractionalconversion.

The branching frequency can then be calculated knowing the molar ratioof monomer 1 to monomer 2 in the polymer:

$\begin{matrix}{{BF} = \frac{500}{Y + 1}} & (10)\end{matrix}$

where Y, is the molar ratio of monomer 1 (ethylene) over monomer 2(1-octene) in the polymer, and BF is the branching frequency (branchesper 1000 carbon atoms).

The overall branching frequency distribution (BFD) of the ethylenecomposition can be calculated by knowing the molecular weightdistribution and weight fraction of polymer made in each reactor, andthe average branching frequency (BF) of the ethylene copolymer made ineach reactor. The fraction of polymer made in each reactor can becalculated from the experimental mass flows and conversion of monomerand comonomer in each reactor. The branching frequency distributionfunction is obtained by calculating the average branch content for eachmolecular weight value of the overall molecular weight distributionfunction made from the two Flory distributions:

$\begin{matrix}{{BF_{MW}} = \frac{{w_{R1}BF_{R1}{F_{1}\left( {MW_{R1}} \right)}} + {w_{R2}BF_{R2}{F_{2}\left( {MW_{R2}} \right)}}}{{w_{R1}{F_{1}\left( {MW_{R1}} \right)}} + {w_{R2}{F_{2}\left( {MW_{R2}} \right)}}}} & (11)\end{matrix}$

where BF_(MW) is the branching at molecular weight (MW), w_(R1) andw_(R2) are the weight fraction of polymer made in Reactor 1 and Reactor2, BF_(R1) and BF_(R2) are the average branching frequency of polymermade in R1 and R2 (from Equations 9 and 10), F₁(MW_(R1)) and F₂(MW_(R2))are Flory distribution function from Reactor 1 and Reactor 2.

The overall branching frequency of the polyethylene composition is givenby the weighted average of the branching frequency of the polymer madein each reactor:

BF _(avg) =w ₁ BF ₁ +w ₂ BF ₂  (12)

where, BF_(avg) is the average branching frequency for the total polymer(e.g. the polyethylene composition), w₁ and w₂ are the weight fractionof material made in each reactor, BF₁ and BF₂ are the branchingfrequency of material made in each reactor (e.g., the branchingfrequency of the first and second ethylene copolymers).

For the polymer obtained in each reactor, the resin parameters which canbe obtained from the above described kinetic model are the molecularweights M_(n), M_(w) and M_(z), the molecular weight distributionsM_(w)/M_(n) and M_(z)/M_(w) and the branching frequency (SCB/1000 Cs).With this information in hand, a component (or composition) densitymodel and a component (or composition) melt index, 12, model was usedaccording to the following equations, which were empirically determined,to calculate the density and melt index I₂ of each of the first andsecond ethylene copolymers:

Density:

$\frac{1}{\rho} = {{{1.0}142} + {{0.0}033\left( {1.22 \cdot {BF}} \right)^{{0.8}346}} + \frac{{0.0}303k^{0.9804}}{1 + \frac{{0.3}712}{e^{{1.2}2BF}}}}$

where, BF is the branching frequency, k=Log₁₀(M_(n)/1000)

Melt Index, I₂ (MI):

${{Log}_{10}({MI})} = {{{7.8}998} - {{3.9}089{{Log}_{10}\left( \frac{M_{w}}{1000} \right)}} - {{0.2}799\frac{M_{n}}{M_{w}}}}$

Hence, the above models were used to estimate the branch frequency,weight fraction (or weight percent), melt index I₂, and the density ofthe polyethylene composition components, which were formed in each ofreactor 1 and 2 (i.e. the first and second ethylene copolymers).

TABLE 2 Reactor Conditions for Examples Example No. Example 1 Example 2Example 3 Example 4 Example 5 Example 6 Reactor 1 Ethylene (kg/h) 40.435.7 35.6 35.6 35.7 24.5 Octene (kg/h) 1.7 1.5 1.9 1.4 2 0.6 Hydrogen(g/h) 1.04 0.7 0.6 0.6 0.7 0.4 Solvent (kg/h) 282 252.8 252.5 253.1252.3 171 Reactor feed inlet 30 30 30 30 30 30 temperature (° C.)Reactor Temperature 163 162.3 162 161.7 162 162 (° C.) Catalyst (ppm)0.1 0.11 0.12 0.12 0.14 0.12 Reactor 2 Ethylene (kg/h) 40.4 43.6 43.643.5 43.5 57 Octene (kg/h) 0 0 0 0 0 0 Hydrogen (g/h) 14.30 13.90 19.2011.50 14.30 6.6 Solvent (kg/h) 102 132 131 131 131 222 Reactor feedinlet 30 30 30 30 30 30 temperature (° C.) Reactor Temperature 205 202202 202 202 203 (° C.) Catalyst (ppm) 0.72 0.56 0.59 0.56 0.57 0.42

TABLE 3 Resin Properties Resin Ex. 1 Ex. 2 Ex. 3 Ex. 4 Ex. 5 Ex. 6Density (g/cm³) 0.9569 0.955 0.9575 0.9559 0.9555 0.9555 Rheology/FlowProperties Melt Index I₂ 7.66 7.21 7.29 4.54 7.17 8.1 (g/10 min) I₅ 21.913.2 23.5 I₂₁ 239 237 312 171 268 228 Melt Flow Ratio (I₂₁/I₂) 31.2 32.842.8 37.8 37.4 28.9 Stress Exponent 1.28 1.31 1.35 1.32 1.33 1.32 ShearViscosity (η) at 10⁵ s⁻¹ 5.9 6.3 4.8 6.2 5.6 6.9 (240° C., Pa-s) 100/ηat 10⁵ s⁻¹ (240° C.), 16.95 15.87 20.83 16.13 17.86 14.49 ProcessabilityIndicator Shear viscosity Ratio 66.4 60.9 79.6 84.5 70 51.78(η₁₀₀/η₁₀₀₀₀₀, 240° C.) GPC M_(n) 13088 16127 11001 16505 14020 23319M_(w) 61162 59330 57976 68596 58484 63204 M_(z) 153222 144200 163371187835 149424 148799 Polydispersity Index 4.67 3.68 5.27 4.16 4.17 2.71(M_(w)/M_(n)) TREF CDBI(50) 71.1 80.3 72 79.5 78 78.9 CDBI(25) 59.5 70.662.4 68.1 68.7 67.2 Branch Frequency - FTIR (uncorrected for chain end—CH₃) Uncorrected SCB/1000C 1.7 1.4 2.1 1.5 1.8 0.9 Uncorrectedcomonomer 0.3 0.3 0.4 0.3 0.4 0.2 content (mol %) Comonomer ID 1-octene1-octene 1-octene 1-octene 1-octene 1-octene Terminal 0.21 0.08 0.090.09 0.08 0.12 unsaturation/1000C Internal 0.09 0.16 0.13 0.14 0.14 0.11unsaturation/1000C Side chain 0 0.01 0.01 0.00 0.01 0 unsaturation/1000CTotal unsaturations/1000C 0.30 0.25 0.23 0.23 0.23 0.23 Comonomer mol %measured by ¹³C-NMR Hexyl+ branches 0.29 0.31 (>=4 C atoms), mol % DSCPrimary Melting Peak (° C.) 129.77 129.72 129.71 130.0 129.46 131.5 Heatof Fusion (J/g) 217.6 214.2 218.8 216.4 215.7 215.6 Crystallinity (%)75.04 73.88 75.44 74.63 74.37 74.33 Hexane Extractables (%) 0.33 ResinExample A Example B Example C Example D Example E Density (g/cm³) 0.95840.9585 0.9591 0.960 0.9540 Rheology/Flow Properties Melt Index I₂ (g/10min) 7.18 7.51 8.56 8.52 9.00 I₅ I₂₁ 229 234 258 222 191 Melt Flow Ratio(I₂₁/I₂) 32 31.2 30.1 26.1 21.2 Stress Exponent 1.28 1.27 1.26 1.29 1.22Shear Viscosity (η) at 10⁵ s⁻¹ 5.8 5.7 6.9 7.9 (240° C., Pa-s) 100/η at10⁵ s⁻¹ (240° C.), 17.24 17.54 14.49 12.66 Processability IndicatorShear viscosity Ratio 54.6 47.9 (η₁₀₀/η₁₀₀₀₀₀, 240° C.) GPC M_(n) 1452613771 13469 17022 20519 M_(w) 64533 62612 59226 63567 59812 M_(z) 166380157914 144926 181472 140168 Polydispersity Index 4.44 4.55 4.40 3.732.91 (M_(w)/M_(n)) TREF CDBI(50) 46.6 45.2 — 68.5 74.6 CDBI(25) 32.429.4 — 53.6 50.7 Branch Frequency - FTIR (uncorrected for chain end—CH₃) Uncorrected SCB/1000C 2.0 2 1.0 Uncorrected comonomer 0.4 0.4 <0.10.2 content (mol %) Comonomer ID 1-octene 1-octene 1-octene 1-butene1-octene Terminal 0.16 0.12 0.14 0.17 0.50 unsaturation/1000C Internal0.08 0.09 0.08 0.04 0 unsaturation/1000C Side chain 0.01 0.01 0.01 00.01 unsaturation/1000C Total unsaturations/1000C 0.25 0.22 0.23 0.210.51 Total unsaturations per 0.26 0.22 0.22 0.26 0.75 number averagemolecule Comonomer mol % measured by ¹³C-NMR Hexyl+ branches (>=4 — — —— — carbon atoms), mol % DSC Primary Melting Peak (° C.) 130.79 130.02132.3 130.8 Heat of Fusion (J/g) 220.9 220.3 217.9 208.7 Crystallinity(%) 76.17 75.96 75.14 72.0 Hexane Extractables (%) 0.44 0.38 0.37

TABLE 4 Polyethylene Component Properties Resin Ex. 1 Ex. 2 Ex. 3 Ex. 4Ex. 5 Ex. 6 Density (g/cm³) 0.9569 0.955 0.9575 0.9559 0.9555 0.9559 I₂(g/10 min.) 7.66 7.21 7.29 4.54 7.17 8.2 Stress Exponent 1.28 1.31 1.351.32 1.33 1.31 MFR (I₂₁/I₂) 31.2 32.8 42.8 37.8 37.4 28.6 Mw/Mn 4.673.68 5.27 4.16 4.17 2.71 First Ethylene Polymer Weight fraction 0.5 0.480.48 0.47 0.47 0.32 Mw 107939 101355 109586 117645 105809 125184 I₂(g/10 min.) 0.65 0.83 0.61 0.46 0.70 0.36 Density, d1 (g/cm³) 0.94210.9414 0.9395 0.9420 0.9402 0.9426 SCB1/1000C 0.66 0.8 0.93 0.59 0.880.48 Second Ethylene Polymer Weight fraction 0.5 0.52 0.52 0.53 0.530.68 Mw 15056 19854 12425 19110 15903 32391 I₂ (g/10 min.) 1433 486 3036564 1157 72 Density, d2 (g/cm³) 0.9630 0.9615 0.9653 0.9621 0.96260.9593 SCB2/1000C 0.49 0.34 0.43 0.31 0.47 0.111 Estimated (d2 − d1),0.021 0.020 0.026 0.020 0.022 0.017 g/cm³ Estimated SCB1/SCB2 1.35 2.352.16 1.90 1.87 4.32 Resin Example A Example B Example C Density (g/cm³)0.9584 0.9585 0.9591 I₂ (g/10 min.) 7.18 7.51 8.56 Stress Exponent 1.281.27 1.26 MFR (I₂₁/I₂) 32 31.2 30.1 Mw/Mn 4.44 4.55 4.4 First EthylenePolymer Weight fraction 0.5 0.5 0.5 Mw 110512 108978 103442 I₂ (g/10min.) 0.59 0.63 0.77 Density, d1 (g/cm³) 0.9503 0.9504 0.9509 SCB1/1000C0 0 0 Second Ethylene Polymer Weight fraction 0.5 0.5 0.5 Mw 14593 1461814581 I₂ (g/10 min.) 1619 1608 1625 Density, d2 (g/cm³) 0.9552 0.95530.9553 SCB2/1000C 2.1 2.07 2.07 Estimated (d2 − d1), g/cm³ 0.005 0.0050.004 Estimated SCB1/SCB2 0.00 0.00 0.00

TABLE 5 Plaque Properties Resin Ex. 1 Ex. 2 Ex. 3 Ex. 4 Ex. 5Environmental Stress Crack Resistance ESCR Cond. B at 100% (hrs.) 4 5 67 5 Flexural Properties (Plaques) Flex Secant Mod. 1% (MPa) 1352 13691460 1352 1308 Flex Sec Mod 1% (MPa) Dev. 58 37 33 76 51 Flex SecantMod. 2% (MPa) 1135 1151 1245 1152 1114 Flex Sec Mod 2% (MPa) Dev. 35 1817 52 34 Flexural Strength (MPa) 39.5 40.1 42.5 40.2 39.2 FlexuralStrength Dev. (MPa) 0.4 0.4 0.5 1.1 0.7 Tensile Properties (Plaques)Elongation at Yield (%) 8 9 8 9 8 Elongation at Yield Dev. (%) 0 0 1 0 0Yield Strength (MPa) 28.2 29.6 31 29.8 29.8 Yield Strength Dev. (MPa)0.8 0.2 0.1 0.2 0.2 Ultimate Elongation (%) 1018 1033 491 1042 995Ultimate Elongation Dev. (%) 39 36 523 105 32 Ultimate Strength (MPa)18.8 18.8 20 23.4 19.1 Ultimate Strength Dev. (MPa) 0.8 0.9 4.7 4.4 0.6Sec Mod 1% (MPa) 1702 1372 1644 1505 1531 Sec Mod 1% (MPa) Dev. 222 81143 94 111 Sec Mod 2% (MPa) 1077 1022 1135 1069 1065 Sec Mod 2% (MPa)Dev. 67 47 57 37 19 Impact Properties (Plaques) Notched Izod Impact(ft-lb/in) 0.8 0.9 0.8 1 0.9 Notched lzod Impact (J/m) 42.72 48.06 42.7253.4 48.06 Resin Example A Example B Example C Example D Example EEnvironmental Stress Crack Resistance ESCR Cond. B at 100% (hrs.) 1 1 15 5 Flexural Properties (Plaques) Flex Secant Mod. 1% (MPa) 1349 13741280 Flex Sec Mod 1% (MPa) Dev. 65 49 62 Flex Secant Mod. 2% (MPa) 11421149 1083 Flex Sec Mod 2% (MPa) Dev. 43 33 50 Flexural Strength (MPa)40.4 40.6 37.9 Flexural Strength Dev. (MPa) 0.7 0.6 1 Tensile Properties(Plaques) Elongation at Yield (%) 9 8 10 Elongation at Yield Dev. (%) 01 1 Yield Strength (MPa) 29 29.1 27.9 Yield Strength Dev. (MPa) 0.4 0.30.5 Ultimate Elongation (%) 450 11 (very 1433 brittle failure) UltimateElongation Dev. (%) 165 1 200 Ultimate Strength (MPa) 14.8 29.1 (very23.9 brittle failure) Ultimate Strength Dev. (MPa) 0.9 0.3 3.7 Sec Mod1% (MPa) 1728 1405 1263 Sec Mod 1% (MPa) Dev. 292 359 404 Sec Mod 2%(MPa) 1106 1038 904 Sec Mod 2% (MPa) Dev. 69 102 116 Impact Properties(Plaques) Notched Izod Impact (ft-lb/in) 0.6 0.6 1 Notched Izod Impact(J/m) 32.04 32.04 53.4

TABLE 6 Dimensional Stability Resin Ex. 1 Ex. 2 Ex 3 Ex. 4 Ex. 5 Ex. 6TD shrinkage, IM disk, 48 hr. 1.67 1.87 1.93 1.71 1.79 1.84 MDshrinkage, IM disk, 1.62 1.72 1.93 1.77 1.77 1.89 48 hr. (TD shrinkage −MD 0.05 0.15 0 −0.06 0.02 −0.05 shrinkage), IM disk, 48 hr. TD/MDshrinkage ratio, 1.03 1.09 1.00 0.97 1.09 0.97 isotropy indicator, IMdisk, 48 hr. Resin Example D Example E TD shrinkage, IM disk, 48 hr.1.82 1.69 MD shrinkage, IM disk, 48 hr. 1.68 1.31 (TD shrinkage − MDshrinkage), IM 0.14 0.38 disk, 48 hr. TD/MD shrinkage ratio, isotropy1.08 1.29 indicator, IM disk, 48 hr.

As can be seen from the data provided in Tables 3-6 and FIGS. 8-10 , thepolyethylene compositions Example 1-6 have very good dimensionalstability, are easy to process (e.g., have good injectability whenmaking an injection molded part), show good organoleptic properties andimpact resistance and have useful ESCR for applications such as bottleclosure assemblies. For example, FIG. 8 shows that relative topolyethylene resins A, B, D (J60-800-178) and E (IG454-A), thepolyethylene compositions 1-5 have an improved balance of processabilityand ESCR. Also, as shown in FIG. 9 , the polyethylene compositions 1-5have a better balance of processability and impact strength whencompared to polyethylene resins A, B, D (J60-800-178) and E (IG454-A).The processability comparison is made on the basis of a “processabilityindicator,” which as used herein, is defined as 100/η at 10⁵ s⁻¹ (240°C.), where η is the Shear Viscosity (η) at 10⁵ s⁻¹ (240° C., Pa-s) asdefined above.

FIG. 10 shows that polyethylene compositions 1 and 2 have a betterdimensional stability (the TD/MD shrinkage isotropy indicator) than apolypropylene homopolymer having a melt flow rate of 35 g/10 min (testedat 230° C. under 2.16 kg). Also polyethylene compositions 1 and 2 havecomparable or better dimensional stability than the polyethylene resin D(J60-800-178) and E (IG454-A).

FIGS. 11 and 12 show that the compositions 1-5 have a good balance oftensile strength or tensile elongation and processability (as indicatedby the “processability indicator”) when compared to polyethylene resinsA, D, and E. Without wishing to be bound by theory, a plastic materialhaving good processability while at the same time having high tensilestrength and elongation at break would be useful in the manufacture of aclosure assembly where a tether portion should be strong enough towithstand normal use and resist abuse without breaking or deforminginappropriately.

Table 6 shows that polyethylene compositions 1-6 generally have betterdimensional stability than resins D and E. Compare, for example,polyethylene compositions 1, 2, 3, 4, 5, and 6 which have a TDshrinkage−MD shrinkage of 0.05, 0.15, 0, −0.06, 0.02, and −0.05respectively with resins D and E which have a TD shrinkage−MD shrinkageof 0.14 and 0.38 respectively. Also compare the TD/MD shrinkage ratio(the indicator of isotropy) for polyethylene compositions 1, 2, 3, 4, 5,and 6 at 1.03, 1.09, 1, 0.97, 1.09, and 0.97 respectively which are allfairly close to 1, with the TD/MD shrinkage ratio (the indicator ofisotropy) for polyethylene resins D and E which are 1.08 and 1.29respectively.

Four additional polyethylene compositions (Examples 7A, 7B, 8, and 9)were made using a single site phosphinimine catalyst in a dual reactorsolution process. Examples 7A and 7B were made substantially asdescribed above for Examples 1-6. Examples 8 and 9 were made using theconditions provided below in Table 7. Each of the Examples 7A, 7B, 8,and 9 have an ESCR (Condition B at 100% IGEPAL® CO-630 at 50° C.) ofgreater than 3.5 hours and a SCB1/SCB2 ratio of greater than 1.0. Theseexamples also have a Mz value of less than 300,000. Examples 7A and 7Bhave a density of 0.957 g/cm³, a melt index I₂ of less than 10 g/10 min,a melt flow ratio I₂₁/I₂ ratio of less than 41. Example 8 has a densityof 0.954 g/cm³, a melt index I₂ of less than 10 g/10 min and a melt flowratio I₂₁/I₂ ratio of less than 41. Example 9 has a density of 0.955g/cm³, a melt index I₂ of 7.6 g/10 min, and a melt flow ratio I₂₁/I₂ of42.4. Table 8 provides further polymer information and plaque data forExamples 7, 8, and 9. Table 9 provides the first and second ethylenecopolymer component properties calculated for Examples 7A, 8, and 9 (see“Copolymerization Reactor Modeling” above for methods).

TABLE 7 Reactor Conditions Example 8 9 Reactor 1 Ethylene (kg/h) 37.1638.07 Octene (kg/h) 1.00 2.02 Hydrogen (g/h) 0.68 0.70 Solvent (kg/h)303.40 312.68 Reactor feed inlet 35.00 30.00 temperature (° C.) ReactorTemperature (° C.) 162.90 163.99 Catalyst-Fresh Ti Feed to 0.10 0.02 R1(ppm) Reactor 2 Ethylene (kg/h) 45.40 46.53 Fresh Octene (kg/h) 0.000.00 Hydrogen (g/h) 7.46 12.35 Solvent (kg/h) 186.80 188.65 Reactor feedinlet 35.00 31.02 temperature (° C.) Reactor Temperature (° C.) 202.50202.63 Catalyst-Fresh Ti Feed to 0.05 0.06 R1 (ppm)

TABLE 8 Polymer and Polymer Plaque Properties Example 7A 7B 8 9 Density(g/cm³) 0.957 0.957 0.9542 0.955 Rheology/Flow Properties Melt Index I₂(g/10 min) 7 7 7.28 7.55 Melt Flow Ratio (I₂₁/I₂) 34.4 36 32.4 42.4Stress Exponent 1.30 1.29 1.35 1.38 Shear Viscosity (η) at 10⁵ s⁻¹ 5.806.1 6.50 5.3 (240° C., Pa-s) Shear viscosity Ratio 69.38 67.4 55.7765.75 (η₁₀₀/η₁₀₀₀₀₀, 240° C.) GPC-conventional M_(n) 17097 14710 2190813852 M_(w) 63337 63008 63412 61543 M_(z) 154296 157796 146082 180184Polydispersity Index (M_(w)/M_(n)) 3.70 4.28 2.89 4.44 M_(z)/M_(w) 2.442.50 2.30 2.93 Branch Frequency-FTIR (uncorrected for chain end —CH₃)Uncorrected SCB/1000C 1.4 1.7 1.3 1.7 Uncorrected comonomer content 0.280.30 0.26 0.34 (mol %) Internal unsaturation (/1000C) 0.050 0.05 0.090.07 Side chain unsaturation (/1000C) 0.010 0 0 0 Terminal unsaturation(/1000C) 0.100 0.10 0.14 0.12 Comonomer ID 1-octene 1-octene 1-octene1-octene TREF CDBI₅₀ (%) 73.2 74.3 84.2 78.2 CDBI₂₅ (%) 60.9 62 74.867.6 DSC Primary Melting Peak (° C.) 131.7 129.98 130.34 129.45 Heat ofFusion (J/g) 225.50 224.2 211.80 220.7 Crystallinity (%) 77.77 77.3073.03 76.10 Environmental Stress Crack Resistance ESCR Cond. B at 100%(hrs) 5 6 4 4 ESCR Cond. B at 10% (hrs) 3 3 Flexural Properties(Plaques) Flex Secant Mod. 2% (MPa) 1209 1170 1051 1133 ImpactProperties (Plaques) Izod Impact (ft-lb/in) 1.0 0.9 1.0 0.8 IZOD DV(ft-lb/inch) 0.1 Other properties Hexane Extractables (%) 0.22 0.16 0.50.21 VICAT Soft. Pt. (° C.)-Plaque 127.8 128 128.3 126.5 Heat Deflection73.3 73 77.8 75.3 Temp. [° C.] @ 66 PSI

TABLE 9 Polyethylene Component Properties Example 7A 8 9 Density (g/cm³)0.9581 0.9542 0.955 I₂ (g/10 min) 7.03 7.28 7.55 Stress Exponent 1.31.35 1.38 MFR (I₂₁/I₂) 34.4 32.4 42.4 Mw/Mn 3.70 2.89 4.44 FirstEthylene Polymer Weight fraction 0.447 0.433 0.433 Mw 119379 115624111125 I₂ (g/10 min) 0.44 0.5 0.58 Density, d1 (g/cm³) 0.9438 0.94200.9395 SCB1/1000C 0.44 0.6 0.91 Second Ethylene Polymer Weight fraction0.553 0.567 0.567 Mw 18458 26168 18721 I₂ (g/10 min.) 646 165 611Density, d2 (g/cm³) 0.9633 0.9594 0.9612 SCB2/1000C 0.23 0.29 0.45Estimated (d2-d1), g/cm³ 0.0195 0.0174 0.0217 Estimated SCB1/SCB2 1.912.07 2.02

The polyethylene compositions described above can be used in theformation of bottle closure assemblies. For example, bottle closureassemblies formed in part on in whole by compression molding and/orinjection molding are contemplated.

In one embodiment, the bottle closure assembly includes the polyethylenecomposition described above which have a good balance of processability,organoleptic properties, dimensional stability, and ESCR values. Hencethe bottle closure assemblies are well suited for sealing bottles,containers and the like, for examples bottles that may contain drinkablewater, and other foodstuffs, including but not limited to liquids thatare non-pressurized.

In an embodiment of the disclosure, a bottle closure assembly includinga polyethylene composition defined as above is prepared with a processincluding at least one compression molding step and/or at least oneinjection molding step.

Preparation of a Tether Proxy for Deformation Testing

In order to provide a proxy of a tether portion which can be analyzedunder conditions of shear, tear, and tensile deformation, a closure (seeFIGS. 13A and 13B) was compression molded as described below and then atamper evident band, 10* (a proxy for a retaining means portion, 10) wasformed by folding in and cutting the bottom circular edge of the closureusing a folding/slitting machine with a modified blade, so that a tamperevident band (10*) which was joined to the cap portion (1) by severalnarrow (“pin” like) connecting sections (marked by the frangible line, 9in FIGS. 13A and 13B) and one larger continuous section (i.e. continuouswith a portion of the cap portion side wall), with the larger continuoussection serving as a proxy for a tether (the area marked as 40 in FIGS.13A and 13B). The larger continuous section or “tether proxy” sectionwas designed to have an arcuate length of 6 mm. The “tether proxy”section had a cross-sectional width (or thickness) of 0.6 mm asdetermined by the dimensions of the closure mold used for thecompression molding process (see below). The “tether proxy” section, orsimply “tether proxy” 40 was then subjected to shear and teardeformations and to tensile deformation using a toque tester unit andtensile tester unit respectively (see below).

Method of Making a Closure by Compression Molding

A SACMI Compression molding machine (model CCM24SB) and a PCO (plasticclosure only) 1881 carbonated soft drink (CSD) closure mold was used toprepare the closures. Depending on material density, melt index (I₂) andchosen plug size, the closure weight varied between 2.15 g and 2.45grams, with the process conditions adjusted to target a closure having aweight of about 2.3 grams. During the closure preparation process, theoverall closure dimensions, such as, for the example, the closurediameter and the closure height were measured and maintained withindesired “quality-controlled” specifications. Closures with poorcircularity or with significant deformation away from the pre-definedspecifications were rejected by an automatic vision system installed onthe compression molding machine. Once the closure had been compressionmolded, a tamper evident band, inclusive of one larger continuoussection (a proxy for a tether portion) was cut into the closure bottomedge using a folding/slitting machine fitted with a modified blade. Bothexperimental and simulated data confirmed that 99% of any closure weightdifferences were due to differences in the top panel thickness of thecap portion (see FIG. 13A) for each of the compression molded closures.For example, in the closures prepared by compression molding, the toppanel thickness values of closures having a weight ranging from 2.15grams to 2.45 grams were found to be slightly different, but each of theclosure side wall thicknesses were found to be identical. As a result,any small differences in the compression molded cap weight were expectedto have no impact on the dimensions of the tamper evident band or thetether proxy section (see above): in each case, the tether proxy had anarcuate length of 6 mm and a cross-sectional thickness of 0.6 mm.

Type 1 closures were compression molded from the polyethylenecomposition of Example 7B which had a melt index, 12 of 7 g/10 min and adensity of 0.957 g/cm³.

Type 2 closures (Comparative) were compression molded from a unimodalpolyethylene copolymer of ethylene and 1-butene having a melt index I₂of 32 g/10 min, a density of 0.951 g/cm³, and a molecular weightdistribution, Mw/Mn of 2.88, and which is made using a Ziegler-Nattacatalyst in a solution olefin polymerization process. This resin iscommercially available from NOVA Chemicals Corporation as SCLAIR 2712.

The compression molding conditions used to make each closure type areprovided in Table 10.

TABLE 10 Compression Molding Processing Conditions Closure Type No. 1 2Closure Weight (g) 2.32 2.39 BT1 Temp (° C.) 164 163 BT2 Temp (° C.) 166164 BT3 Temp (° C.) 160 163 BT4 Temp (° C.) 162 161 BT6 Temp (° C.) 170170 BT7 Temp (° C.) 182 187 BT8 Temp (° C.) 183 184 BT9 Temp (° C.) 182184 BT15 Temp (° C.) 170 170 BT16 Temp (° C.) 165 165 BT17 Temp (° C.)174 174 Metering Pump Set Press (bar) 50 50 Metering Pump Actual Press 1(bar) IN 48.5 50 Metering Pump Actual Press 2 (bar) OUT 52.4 30.6 PumpSpeed (%) 56 57 Hydraulic Operating Temp (° C.) 46 46 Punch Cooling BT18(° C.) 20 20 Cavity Cooling BT19 (° C.) 20 20 Ausiliari Cooling BT20 (°C.) 30 30

Shear Deformation of a Tether Proxy

A TMS 5000 Torque Tester unit manufactured by Steinfurth was used tocarry out the tether proxy shear deformation testing. The unit wasadjusted to operate in “removal torque mode”. A closure having a tetherproxy section (area 40 in FIGS. 13A and 13B) with a 6 mm arcuate lengthand a 0.6 mm cross-sectional width connecting a cap portion (1) to atamper evident band 10* (a proxy for a retaining means portion, 10) andsuitable for mating with a PCO 1881 bottle finish was employed. Prior totesting, the tamper evident band (10*) was unfolded and then almostentirely removed, by cutting through the tamper evident band at adistance of approximately 2 mm from each end of the tether proxysection. The remaining portion of the tamper evident band (as shown inFIGS. 14A and 14B) then, includes the tether proxy section having anarcuate length of 6 mm, and a further 2 mm arcuate length section oneither side of the tether proxy section, all of which has a crosssectional width of 0.6 mm. Adding 2 mm to either side of the tetherproxy section provides a larger surface area to grip when carrying outthe shear deformation testing. In order to support the closure fortesting in the Torque Tester unit, a modified tubular preform was used(item 45 in FIG. 14B). The tubular pre-form 45 was made of polyethyleneterephthalate and was modified to have smooth outer walls. Followingthis, a brass rod (50), having a diameter which fit snuggly within thepreform (45) was inserted as a plug to afford rigidity to the pre-formand to prevent its deformation during testing. Next, the closure wasplaced on top of the pre-form and the remaining section of the tamperevident band (10*) was clamped to the preform using vice grips. Theclosure and preform were then mounted within the Torque Tester. The capportion (1) was gripped from above within a suitably designed chuck androtated at a removal torque speed of 0.8 rpm, relative to the clampedsection of the tamper evident band, using the Torque Tester. The shearstrength of the tether proxy (40) is defined as the maximum torque (ininches·pounds) required to separate the cap portion (1) from theremaining section of the tamper evident band section (10*) by breakingthe tether proxy (40). The reported shear strength in Table 11 is theaverage of at least 5 such shear deformation tests.

Tear Deformation of a Tether Proxy

A TMS 5000 Torque Tester unit manufactured by Steinfurth was used tocarry out the tether proxy shear deformation testing. The unit wasadjusted to operate in “removal torque mode”. A closure having a tetherproxy section (area 40 in FIGS. 13A and 13B) with a 6 mm arcuate lengthand a 0.6 mm cross-sectional width connecting a cap portion (1) to atamper evident band 10* (a proxy for a retaining means portion, 10) andsuitable for mating with a PCO 1881 bottle finish was employed. In orderto support the closure for testing in the Torque Tester unit, a modifiedtubular pre-form was used (item 45 in FIG. 14C). The tubular pre-formwas made of polyethylene terephthalate and was modified to have smoothouter walls. Following this, a brass rod (50), having a diameter whichfit snuggly within the pre-form (45) was inserted as a plug to affordrigidity to the pre-form and to prevent its deformation during testing.Next, the closure was placed on top of the preform. Prior to testing,the tamper evident band (10*) was deflected downward (on the oppositeside of the tether proxy section) and away from the cap portion (1) asis shown in FIG. 14C. The downward deflection breaks all the narrow pinsections (the frangible line 9 in FIGS. 13A and 13B) joining the topedge of the tamper evident band to the lower edge of the cap portionwhile leaving the larger continuous section, the tether proxy section(40), intact. The tamper evident band (10*) is deflected downward andaway from the cap portion (1) until the top edge of the tamper evidentband makes an angle with the lower edge of the cap portion of about 27degrees, while the tether portion remains intact along its 6 mm arcuatelength (see FIG. 14C). The tamper evident band (10*) was then clamped tothe pre-form in this downwardly deflected position using vice grips. Theclosure and pre-form were then mounted within the Torque Tester. The capportion (1) was gripped from above within a suitably designed chuck androtated at a removal torque speed of 0.8 rpm, relative to the clampedtamper evident band (10*), using the Torque Tester. The tear strength ofthe tether proxy (40) is defined as the maximum torque (ininches·pounds) required to separate the cap portion (1) from thedownwardly deflected tamper evident band (10*) by breaking the tetherproxy (40). The reported tear strength in Table 11 is the average of atleast 5 such tear deformation tests.

Tensile Deformation of a Tether Proxy

Tensile deformation tests were performed using a tensile machine (anInstron 4204 universal tester, with a 1 KN (225 lbf) capacity load cell)with the crosshead velocity set at 50 mm/min. A closure having a tetherproxy section (area 40 in FIGS. 13A and 13B) with a 6 mm arcuate lengthand a 0.6 mm cross-sectional width connecting a cap portion (1) to atamper evident band 10* (a proxy for a retaining means portion, 10) andsuitable for mating with a PCO 1881 bottle finish was employed. Prior totesting, the tamper evident band (10*) was unfolded and then almostentirely removed, by cutting through the tamper evident band at adistance of approximately 2 mm from each end of the tether proxy section(see FIGS. 14A, 15A, and 15B). The remaining portion of the tamperevident band (as shown in FIGS. 14A, 15A, and 15B) then, includes thetether proxy section having an arcuate length of 6 mm, and a further 2mm arcuate length section on either side of the tether proxy section,all of which has a cross sectional width of 0.6 mm. Adding 2 mm toeither side of the tether proxy section provides a larger surface areato grip when carrying out the tensile deformation testing. For thetensile deformation test, most of the cap portion (1) was similarly cutaway, leaving only a section of the cap portion side wall connected tothe what was left of the tamper evident band (see FIGS. 15A and 15B).This “cut away” section of the closure was then mounted in the tensiletester, with the remaining cap portion side wall and the remainingtamper evident band each being secured with 0.5-inch wide steel serratedgrips at a 0.25-inch grip separation. During the tensile testing, theremaining section of the cap portion (1) and the remaining section ofthe tamper evident band (10*) were drawn apart vertically. The tensilestrength of the tether proxy (40) is defined as the maximum load (ingrams·force, gf) required to separate the remaining cap portion (1) fromthe remaining tamper evident band section (10*) by breaking the tetherproxy (40). The reported tensile strength in Table 11 is the average ofat least 5 such tensile deformation tests.

TABLE 11 Average Shear, Tear, and Tensile Deformation of a Tether Proxy2 Closure Type No. 1 (Comparative) Shear Strength 10.48 9.43 (inches ·pounds) Tear Strength 10.51 9.18 (inches · pounds) Tensile Strength15122 12800 (grams · force)

A person skilled in the art will recognize from the data provided inTable 11, that a tether proxy made using a polyethylene compositionaccording to the current disclosure may have a relatively good abilityto resist shear, tear, and tensile deformations (relative to acomparative tether proxy made from a unimodal polyethylene copolymer ofethylene and 1-butene, SCLAIR 2712). The data thus provides furtherevidence that the polyethylene compositions described herein may beuseful in the production of bottle closure assemblies, by preventingfacile separation of a cap portion from a retaining means portion orfrom a bottle, and by generally helping to prevent loss ordisassociation of a cap portion (a potential plastic waste stream) froma bottle, where the cap portion could otherwise contribute toenvironmental waste concerns.

The present disclosure has been described with reference to certaindetails of particular embodiments thereof. It is not intended that suchdetails be regarded as limitations upon the scope of the disclosureexcept insofar as and to the extent that they are included in theaccompanying claims.

1-7. (canceled)
 8. A bottle closure assembly comprising: an integrallymolded: cap portion, tether portion, and retaining means portion; thecap portion being molded to reversibly engage and cover a bottleopening, the retaining means portion being molded to irreversibly engagea bottle neck or an upper portion of a bottle, and the tether portionbeing molded to connect at least one point on the cap portion to atleast one point on the retaining means portion; wherein the integrallymolded: cap portion, tether portion, and retaining means portion aremade from a polyethylene composition comprising: (1) 10 to 70 wt. % of afirst ethylene copolymer having a melt index I₂, of 10 g/10 min or less;and a density of from 0.920 to 0.960 g/cm³; and (2) 90 to 30 wt. % of asecond ethylene copolymer having a melt index I₂, of at least 50 g/10min; and a density higher than the density of the first ethylenecopolymer, but less than 0.970 g/cm³; wherein a ratio (SCB1/SCB2) of thenumber of short chain branches per thousand carbon atoms in the firstethylene copolymer (SCB1) to the number of short chain branches perthousand carbon atoms in the second ethylene copolymer (SCB2) is greaterthan 0.5; and wherein when the polyethylene composition is molded into aclosure having a tether proxy section with a 6 mm arcuate length and a0.6 mm cross-sectional width, the tether proxy has a shear strength ofat least 10.48 inches·pounds in a shear deformation test, a tearstrength of at least 10.51 inches·pounds in a tear deformation test, anda tensile strength of at least 15122 grams·force in a tensiledeformation test.
 9. The bottle closure assembly of claim 8, wherein thefirst and second ethylene copolymer comprise polymerized ethylene and atleast one polymerized alpha-olefin comonomer, wherein the polymerizedethylene is the majority species.
 10. The bottle closure assembly ofclaim 9, wherein the at least one polymerized alpha-olefin comonomer is1-octene.
 11. The bottle closure assembly of claim 8, wherein thepolyethylene composition has a tensile ultimate elongation of at least600 percent.
 12. The bottle closure assembly of claim 8, wherein thepolyethylene composition has a tensile ultimate strength of at least 16MPa.
 13. The bottle closure assembly of claim 12, wherein thepolyethylene composition has a tensile ultimate strength of at least 16MPa.
 14. The bottle closure assembly of claim 8, wherein thepolyethylene composition comprises: (1) 10 to 70 wt. % of a firstethylene copolymer having a melt index I₂, of from 0.1 to 10 g/10 min; amolecular weight distribution M_(w)/M_(n), of less than 3.0; and adensity of from 0.930 to 0.960 g/cm³; and (2) 90 to 30 wt. % of a secondethylene copolymer having a melt index I₂, of from 50 to 10,000 g/10min; a molecular weight distribution M_(w)/M_(n), of less than 3.0; anda density higher than the density of the first ethylene copolymer, butless than 0.966 g/cm³; wherein the density of the second ethylenecopolymer is less than 0.037 g/cm³ higher than the density of the firstethylene copolymer; the ratio (SCB1/SCB2) of the number of short chainbranches per thousand carbon atoms in the first ethylene copolymer(SCB1) to the number of short chain branches per thousand carbon atomsin the second ethylene copolymer (SCB2) is greater than 1.0; and whereinthe polyethylene composition has a molecular weight distributionM_(w)/M_(n), of from 2 to 7; a density of at least 0.950 g/cm³; a highload melt index I₂₁, of from 150 to 400 g/10 min; a Z-average molecularweight Mz, of less than 300,000; a melt flow ratio I₂₁/I₂, of from 22 to50; and a stress exponent of less than 1.40; a stress exponent of lessthan 1.40; and an ESCR Condition B (100% IGEPAL® CO-630) of at least 3.5hrs.